FRONTLINE

>> It was one of the worst terrorist attacks before 9/11.

>> Pan Am Flight 103 plunged into a small Scottish town.

>> Tonight, Frontline presents... >> All these years later, the case still open.

>> ...the final chapter of this special series.

>> The government has moved on, the FBI has moved on... >> Filmmaker Ken Dornstein's search for those responsible for the murder of 270 people, including his brother.

>> Frontline is made possible by contributions from viewers like you.

Thank you.

And by the Corporation for Public Broadcasting.

Major support for Frontline is provided by the John D. and Catherine T. MacArthur Foundation.

Additional support is provided by the Park Foundation, the John and Helen Glessner Family Trust, the Ford Foundation, the Wyncote Foundation, and by the Frontline Journalism Fund, with major support from Jon and Jo Ann Hagler.

>> Previously on "My Brother's Bomber"... >> There was a man there, and he was still in the same office, same place where the timer that they say had blown up Flight 103.

>> Wow.

>> DORNSTEIN: It looks suspicious, like you are helping the Libyans make the bomb that blew up Flight 103.

>> No, no, no, no... >> DORNSTEIN: I just want one person to tell me that the story is true and I'll let it drop.

I don't need the whole picture, I just want one guy.

And then I'd feel like I'd be done.

Am I going to make a scene and go into the room and say, "Did you murder my brother?"

>> Because you don't bring a bomb as a bomb.

You have to put it together.

>> DORNSTEIN: So there was a bomb expert?

>> A Libyan bomb expert, yes.

>> DORNSTEIN: So the hunt is on for Abu Agela?

>> If he's still alive.

(Internet phone ringing) >> Hi, Dad.

>> DORNSTEIN: Hi, guys.

>> Dad, we can't actually see your eyes.

We can just see your nose and mouth.

Move down.

>> There you are.

Where are you now?

Do you even know where Dad is?

>> Washington, D.C. >> So, what are you doing in Washington?

>> DORNSTEIN: That's a really good question.

Well, there's gonna be a whole ceremony at a big cemetery.

You know, there's like the one national cemetery?

>> Yeah, Arlington Cemetery.

>> DORNSTEIN: Arlington National Cemetery.

They put up a monument for this bombing that killed Uncle David.

And now 25 years later all the families are gonna come, and, uh, I'm gonna show up for Uncle David.

Can you guys imagine still caring about a story even 25 years later?

>> Yes.

>> Yeah, if it made my brother die.

>> DORNSTEIN: Yeah.

>> 25 years ago tomorrow, four days before Christmas, a bomb exploded aboard a Pan Am jetliner over Lockerbie, Scotland.

>> All 259 on board, mostly Americans, and 11 on the ground were killed.

>> And on this anniversary, they will gather once more, mindful that 25 years later, justice has not been done for those lost at Lockerbie.

>> It's hard to believe that a quarter of a century has gone by and the family members are still asking why, still asking what happened.

>> The past few minutes, a moment of silence has been held in London, Lockerbie, and Arlington Cemetery, to mark the time at three minutes past 7:00 in 1988, when the bomb exploded on board.

>> As they gathered around the memorial in Arlington National Cemetery, a bell was rung as the name of each victim was read aloud.

>> Lockerbie's been a huge part of my life, and always will be.

>> DORNSTEIN: Mine too.

>> Yeah, I get that.

>> DORNSTEIN: 'Cause I've been on this trail for a while, you know, trying to find the few guys left who were probably on your list.

>> Yup.

Someone told me recently that the U.S. government still wants to try to find out more things about Lockerbie.

So I feel good about that, this is an FBI agent telling me that.

He said we were going to go conduct additional investigation.

I hope it's true.

I hope when Mueller leaves the Bureau next year that it doesn't stop.

>> Through the years, Robert Mueller has joined families in honoring the victims.

25 years later, Mueller says, the hunt for the bombers goes on.

>> There are a number of people that we are still seeking.

This investigation is ongoing.

And we will do what we can to assure that others involved in some way, shape or form are prosecuted and successfully tried.

>> The aircraft came out of the sky trailing flames, scattering wreckage, fuel, and passengers.

>> A crater 20 feet deep marks the spot near the main Glasgow road where the jumbo jet came down.

>> The bomb was so powerful... >> DORNSTEIN: 25 years later, why is it that some people can make a kind of peace with it, and other people keep digging around for the truth or justice or the facts or the perpetrators...?

>> Why do we have to do it?

I don't know the answer to that.

I suppose it's partly the type of people we are.

In my case I think the campaign has also been the way of coping with the loss of a dearly loved daughter.

But I suppose you have to balance the harm it's doing to you and those you love against the good that it might produce in the end if you can crack it.

>> DORNSTEIN: There were times I wished I'd never gone to Libya, that I'd never re-opened all of these questions.

Lockerbie had become a puzzle that I told myself I was always just on the verge of solving, but there was always a missing piece.

(shouting on computer screen) In the end, I decided to limit my focus to just one of the suspects on my list: the mystery man who was on the same flight with the convicted bomber, Megrahi, on the morning of Lockerbie and may well have been with him the day he returned home.

The man I suspected of being the Libyans' bomb expert.

Tell me about this Mas'ud Abu Agela.

>> Yeah, we were very keen to account for his movements.

He would pop up in various places.

He very much was, explosives-wise, deeply involved in it.

>> Abouagela Mas'ud, I think is what we always called him.

>> DORNSTEIN: Right.

Was he someone that you actually spoke about during the investigation?

>> Absolutely.

There was an intelligence assessment at the time that he was a technical expert.

And we just could never identify him.

The guy just was sort of a ghost, nobody would acknowledge him.

Even after the Scots went to Libya in 1999 and they asked about Mas'ud, they said they never heard of him.

>> DORNSTEIN: But, if you could figure out who he was, he was probably important.

>> Yeah.

Absolutely.

He was somebody that maybe had something to do with arming the bomb.

>> Give me the passport, American, and for you.

>> You need help?

>> DORNSTEIN: No, no, very good.

Thank you.

>> The U.S. military, of course, helped with the downfall of the Libyan dictator, Moammar Qaddafi, but since then, Libya has become a country without laws.

>> DORNSTEIN: Tripoli, Libya, 2012-- it was now my third time into the country.

This time, though, I was looking mainly for one thing-- to pick up the trail of the Libyan bomb expert Abu Agela.

But things here had changed pretty significantly, my friend Suliman told me.

I mean, what was the security picture at that point?

>> Non-existent.

>> You know there was so many groups fighting for turf.

I mean, the government was trying to take control of the armed groups, but the armed groups were overwhelming them.

I mean, Tripoli was very difficult at that time because there were nightly clashes, there were small militias fighting for, you know, this headquarter and that headquarter.

And then you have the out-of- town militias who have their own turfs in different part of the city.

It was just...

It was crazy.

>> DORNSTEIN: I still wanted to find out something official about Abu Agela.

But now I would need the help of one of the dozens of militias that controlled Tripoli.

>> Everybody has a militia and everybody's ruling a neighborhood and everybody's doing whatever the hell they want.

There's no central authority.

There's no clarity of who's in charge.

>> DORNSTEIN: This is huge.

>> This is warehouse, you see.

>> Even the files of the old intelligence services and the official files of Qaddafi have disappeared.

I know some militias who are selling them in pieces.

There's a warehouse in Tripoli where you can go and you pay a certain fee at the door, and you go into this warehouse where there are piles of official papers.

Some of them are completely insignificant.

Some of them are significant.

And you go in there and you dig for whatever paper you want.

Come, Ken.

His name Bashir... >> DORNSTEIN: I never found the warehouse selling documents that had anything to do with Lockerbie.

But I still looked through every paper I could find that might offer a clue about the suspected bomb maker I was looking for.

There may be documents out there that are relevant, but where are they now?

>> Maybe some have been destroyed or just thrown in the garbage.

Because they were old documents and they meant nothing to them.

To find those names in there, it's like finding a needle in the middle of hay, so it was difficult.

>> All this files, all this.

That's files.

>> I remember the frustration of the last trip.

We were really depressed about the rise of militias and Islamic extremists and whatnot.

The stability, for Libyans, we took that for granted.

I think everybody in the world takes it for granted.

But once it's taken from you, you know, the lawlessness, basically, if something happens to you, there is nobody that you can report it to.

There is no justice to be had.

>> DORNSTEIN: Then, later that year, the news from Libya grew worse.

>> We are coming on the air because we have just learned that the U.S. ambassador to Libya has been killed.

It happened overnight, when angry militants stormed the U.S. consulate in Benghazi, Libya.

They fired shots, set the building on fire.

This is the first U.S. ambassador killed on duty in an attack since 1979.

>> The U.S. is very fearful this will continue.

They consider this an extremely dangerous situation.

>> It's really sad to see, a country that had the opportunity to really start a whole new process.

And they had the money.

Libya was not Egypt or Tunisia.

Libya had oil pumping every day.

But then it sort of descended into this real mess.

I mean, I'm telling you inside Libya there's no way you're going to figure this Lockerbie thing out.

The only place that I will advise anybody investigating this is to go through the people from the Qaddafi regime who fled the country.

A lot of them left.

>> DORNSTEIN: Libya was no longer where I was likely to find the men I was looking for.

I couldn't pick up any trace of the suspected bomb expert, Abu Agela.

But I heard rumors that another of the men on my list, someone with a record of supplying explosives to terrorists, had fled the country, maybe to Cairo.

But his trail had gone cold too.

There was one major figure on my list who definitely fled the country.

And not long after my last trip into Libya, he was finally captured and brought back for trial.

>> It was a humbling return home for Abdullah al Senussi, once one of the most feared people in the country now surrounded by Libyans chanting for justice and revenge.

Senussi is alleged to have been one of the masterminds behind the Lockerbie attack.

He knows the old regime's... >> DORNSTEIN: I felt sure Senussi knew the truth about Lockerbie, but would he ever tell it?

And what about the rest of these three dozen men on trial-- what did they know?

I knew only one person who had contact with these former Qaddafi officials personally-- Libya expert Hafed Al Ghwell.

>> These men believed, "I didn't do anything wrong.

"I was a part of a government.

I represented my nation."

And, you know, "I don't believe I did anything wrong."

I mean, some of these guys killed for Qaddafi, you know, in the '70s and '80s.

Qaddafi knew they will always be loyal to him.

Because everything they have comes from him.

>> The Reagan administration sees Colonel Qaddafi as public enemy number one because he supports worldwide terrorism... >> This mad dog of the Middle East has a goal of a world revolution, Muslim fundamentalist... >> DORNSTEIN: The seeds of Lockerbie, I've come to believe, were sown during the days when President Reagan and Moammar Qaddafi became locked in an escalating war of words and attacks.

>> The leaders of the Western world have called you a terrorist, Colonel Qaddafi.

>> Dressed in a designer jumpsuit and sporting sunglasses... >> DORNSTEIN: How did this guy come to be known to Americans as this almost cartoonish, but dangerous figure?

>> This is the persona Qaddafi wanted.

"This is how I'm going to make a mark on the world stage."

And he started picking fights with the United States.

For no reason.

>> There was a lot of concern by advisers to President Reagan at the time that you had to do something about Libya.

>> The Libyan leader, Colonel Qaddafi, is being blamed for the hijacking.

>> It was an unceasing series of tests by Qaddafi.

>> The finger of suspicion is pointing hard tonight at Moammar Qaddafi, the Libyan leader, in connection with Wednesday's nightclub explosion.

>> Friday's bloody terrorist attacks on airports in Vienna and Rome.

>> Mr. Qaddafi must know that we will hold him fully accountable for terrorist operations against Americans.

>> Several administration officials fanned out on Capitol Hill.

>> There were policy meetings going on at the White House in the National Security Council.

All I can tell you is that there was a debate between people who wanted to kill Qaddafi and people who just wanted to scare him.

>> Qaddafi picked the fight.

It wasn't the U.S. fault.

The fault of the U.S. is it reacted to him.

>> It was called Operation El Dorado Canyon.

The attack on Libya almost 24 hours ago has left many Libyans dead or injured.

>> Last night's raid took a heavy toll here.

Libyan officials... >> We bombed Libya because this was the last straw in a whole series of things that Qaddafi had done.

>> I warned Colonel Qaddafi we would hold his regime accountable.

He did open hostilities, and we closed them.

>> Libyan radio is quoted as saying that one of Moammar Qaddafi's houses was hit and... >> The bombing of '86 had a huge impact on Qaddafi's psyche.

>> If the Americans were trying to wipe out Colonel Qaddafi's home, they couldn't have gotten much closer... >> It was a ten-minute bombing raid.

He disappeared underground.

Even his inner circle didn't know exactly where he was for about three-and-a-half months.

And I know somebody who saw him during that period.

He said he was completely devastated.

He was in a massive depression.

And could not believe that no matter what, this is politics, why are they trying to kill me and kill my family?

>> If the American warplanes were aiming to hit security force headquarters nearby, they missed badly.

Instead, they destroyed civilian homes.

>> Before 9/11, that was the only official time I know of that we bombed a country because of terrorism.

Was that a good way of dealing with terrorism, go bombing people?

I don't think that people generally understood that Pan Am 103 was revenge for that 1986 bombing, but it was.

>> Abu Shalgam, one of Colonel Qaddafi's most senior diplomats ready to talk about revenge.

>> We said that we will attack any place.

I think I am clear.

>> DORNSTEIN: Abdel Rahman Shalgam later renounced Qaddafi, but as Libya's ambassador in Rome back in 1986, he threatened revenge for the U.S. attack.

>> This is the largest Libyan people's bureau in Europe.

>> DORNSTEIN: He said Libyan embassies around the world were put on alert to look for American targets.

>> DORNSTEIN: And so the message was, there will be revenge?

>> Exactly.

>> The mass funeral was for victims of Monday night's air raid.

Coffins were carried along to anti-American chants.

>> DORNSTEIN: And you mentioned someone pledging revenge?

>> Yeah, Said Rashid.

>> DORNSTEIN: You said, if Libya was involved in Lockerbie, Said Rashid could have sort of organized it... >> Yeah, exactly.

>> DORNSTEIN: He could plan out the different parts of a complicated operation?

>> Exactly.

>> DORNSTEIN: Shalgam said he tried often to get answers about Lockerbie from key members of the Qaddafi inner circle, like Abdullah Senussi.

>> DORNSTEIN: About Lockerbie?

>> About Lockerbie.

>> DORNSTEIN: But Shalgam was much more certain about the Libyan role in another attack against Americans two-and- a-half years before Lockerbie.

>> DORNSTEIN: The La Belle Disco?

>> It was around 2:00 a.m. when the bomb went off in the crowded La Belle discotheque.

Police say there were about 500 people inside, many of them off-duty U.S. soldiers.

>> DORNSTEIN: The cycle of revenge that ended in Lockerbie likely began here in Germany, when U.S. servicemen at a Berlin nightclub were attacked in April of 1986.

>> The evidence is now conclusive that the terrorist bombing of La Belle Discotheque was planned and executed under the direct orders of the Libyan regime.

Orders were sent from Tripoli... >> DORNSTEIN: What interested me were clues that several of the men on my list were also involved in the disco bombing.

Said Rashid seems to have led the attack, but was never prosecuted.

But there was another man who worked for him on the disco bombing, and this man would ultimately become the most significant figure in my search for answers about Lockerbie.

>> Police have arrested a Libyan man suspected in the 1986 bombing of a discotheque in Berlin-- a bombing widely seen as an attack against the United States.

The man's name?

Musbah Abulgassem Eter.

The disco where the bomb went off was a hangout for... >> DORNSTEIN: As it happened, I was able to track down Musbah Eter in Berlin in 2012, and he was willing to talk with me.

>> DORNSTEIN: Musbah Eter had spent years in a German prison for the disco bombing.

When I met him, though, his job involved checking up on Libyan revolutionaries injured in the war against Qaddafi.

Okay, and we're gonna film, and that's okay?

We have your permission?

>> Okay.

>> DORNSTEIN: Okay.

Eter agreed to let me film with him as he made his rounds at the clinics.

At this point, he knew I was a journalist who'd been to Libya, but he didn't know that I wanted to talk with him about Lockerbie.

My hope was to build some trust with Eter first before we settled into our roles as victim and perpetrator.

>> DORNSTEIN: By all accounts, Eter had helped arrange medical treatment for these men in Berlin, and they seemed genuinely grateful.

But I wondered if they knew about Eter's ties to the Qaddafi government that they'd just fought so hard to overthrow.

I tried myself to understand Eter's past.

Musbah Eter arrived in Germany in 1984-- an intelligence operative working undercover at the Libyan embassy along with dozens of others, all of whom were under surveillance by the East German secret police, the Stasi.

By late March of 1986, Eter was deeply involved with the plot to bomb the Berlin disco.

Some ten years later, he'd confessed to the German authorities.

And it was in that confession where Eter first mentioned a Libyan bomb expert who played a key role in the plot.

>> Eter described a Libyan who brought the bomb and instructed him how to assemble it.

How to put it together in the end, the individual parts of an explosive device.

>> DORNSTEIN: So there was a Libyan bomb expert.

>> A Libyan bomb expert, yes.

>> DORNSTEIN: Do you remember the name of that person?

>> Eter always referred to him as Abu Gela.

And, of course, sorry, as a German prosecutor, I have no idea how to spell Abu Gela.

I would probably spell it like jelly or something, so I asked him, put it down, please.

And this is what he did.

He wrote "neger," black skin.

But here in German, it doesn't have that negative meaning it has in the U.S. >> DORNSTEIN: And that's the only description he wrote there of him so it must be his most important feature.

>> Yes, yes.

>> DORNSTEIN: That he's very dark skinned.

>> Mm-hmm.

Eter's story was credible.

It was highly accurate and it fit in with the information we had obtained through the Stasi files.

>> DORNSTEIN: More La Belle files.

>> This is only part of it.

>> DORNSTEIN: The Stasi had a lot of information about the Libyans, I gather.

>> The Stasi had a lot of information on the Libyans.

>> DORNSTEIN: The East German secret police, the Stasi, kept a close watch on the Libyans in East Berlin back in the 1980s, and they had the La Belle suspects under close surveillance before and after the bombing.

A lot of the most sensitive files they compiled were likely destroyed.

But enough were preserved to help make the case against the Libyans for La Belle.

And I was hoping there were still enough documents left to make the key link to Lockerbie.

Could we see one?

To my surprise, I was able to find Abu Agela's name all over the Stasi files.

After the disco bombing, it seemed, he stayed in room 526 of Berlin's Metropole Hotel.

He used various code names and aliases, but the Stasi was also able to record his real Libyan passport number: 835004.

And this number turned out to be exactly what I was looking for-- the missing piece of a puzzle I'd been trying to assemble for years.

You know, I looked at the Stasi files and I was surprised to see this Abu Agela and his passport number there.

>> Mm-hmm.

>> DORNSTEIN: Because in the Lockerbie case there were C.I.A.

cables that describe his Abu Agela's name and his role and that showed his passport number and there was a match.

Would that surprise you, that the bomb expert in La Belle was also involved in Lockerbie?

>> Of course I'm not surprised that Abu Agela would also do the same for other bombs, including Lockerbie.

>> DORNSTEIN: So what did all of this really mean?

I kept coming back to those images I'd gotten out of State TV in Libya.

More specifically, I was focused on the man I believed was Abu Agela there in the backseat greeting Megrahi when he returned home.

Records show that Megrahi and Abu Agela were traveling on the same flight several times before Lockerbie, flying in and out of the island of Malta, where the bomb was said to have originated.

In the days and weeks before the bombing, the CIA's informant at the Malta airport suspected that Megrahi and Abu Agela were planning some type of special operation.

>> We absolutely were convinced that he was involved and that he may have been the guy that wired up the bomb, that did all the technical stuff with the explosive.

But we had no other... We didn't know who else he was.

>> DORNSTEIN: Basically this C.I.A.

assessment tells the story...

I walked the original Lockerbie investigators through the trail that led me to the Libyan bomb expert.

>> And Mas'ud.

>> DORNSTEIN: And Mas'ud Abu Agela, passport number 835004.

It's the same as the Stasi documents.

>> Mm, hmm.

>> DORNSTEIN: So Megrahi is traveling twice before Lockerbie with the bomb expert from La Belle Disco.

>> That's pretty interesting.

Would have been great to have known all that.

That's amazing.

>> DORNSTEIN: So, during the La Belle investigation, they find some Stasi documents.

This is from April of '86.

This is the week after La Belle Disco.

And then you find this name.

>> Hmm.

>> DORNSTEIN: And you find the passport number.

>> 835004.

Is that the same?

Yes, certainly is.

>> DORNSTEIN: There's a solid connection here.

There's the same passport number.

>> It's a hell of a coincidence.

>> DORNSTEIN: And there is a witness in Berlin.

His name is Musbah Eter.

He's the Libyan who confessed in the La Belle case who names Abu Agela.

He looks like this.

And Eter... >> And what does he say?

He says basically Abu Agela armed the bomb for the La Belle disco?

>> DORNSTEIN: Yeah, it's in German, but I'll give you from the English side.

>> You know, if agents brought me this now, and I'm not there, I don't know what the... >> DORNSTEIN: But as a prosecutor assessing what... >> You find out.

You go talk to this guy; you find out what he says.

You get his story down, and you try and figure out how you can corroborate it.

>> DORNSTEIN: I returned to Berlin several times to learn more from Musbah Eter.

At this point, I'd told him my brother had been killed in the Lockerbie bombing and that I was hoping he might be able to help me find the truth.

>> DORNSTEIN: He took me to the building where he and Abu Agela had worked together in the mid-1980s.

>> DORNSTEIN: I was hoping he would tell me more about Lockerbie.

But then in the middle of our filming, Eter struck up a conversation with a businessman who now worked at the old embassy.

>> DORNSTEIN: Eter persuaded the businessman to take him inside, and back in his old office, Eter kept getting deeper into the details of what he had done here.

>> DORNSTEIN: I knew what Eter had done in the 1980s-- he struck me as no different than the men on my list.

And maybe his explanation for why he'd once blown up Americans was no different from what the actual Lockerbie bombers might have told me as well.

But I still wanted more.

I still wanted to find the bomb maker, Abu Agela, and Eter, to my surprise, told me that he would help.

He suggested I give him a few months to make contact with Abu Agela, and then we should meet again in Berlin.

>> Want me to call him?

>> DORNSTEIN: What did he say the last time?

>> The last time he said that he's fine doing it.

>> DORNSTEIN: He said he would do it?

>> Yeah, he had no problem with it.

So maybe he's busy.

>> DORNSTEIN: Eter promised to sit for an interview laying out everything he knew about the Libyan bomb maker's role in Lockerbie.

But several times, we planned to meet, and several times, he canceled.

Should we get out of here?

>> Let's get of here.

But let's not give up.

>> DORNSTEIN: At this point, Musbah Eter was my only link to the man I believed helped prepare the Lockerbie bomb.

Back in Berlin, he'd assured me that the "dark skinned" bomb expert was still alive and still in Libya.

I now started to wonder if Eter would be willing to work directly with the U.S. government to pursue Abu Agela.

>> I guess the number one question I would have is can we have access to this guy?

If Ken Dornstein can go talk to him... >> DORNSTEIN: Right.

>> I guess the next question is, what kind of cooperation can the U.S. government or the Scots get in getting access to Abu Agela?

>> DORNSTEIN: Right, right.

>> I mean, this isn't easy, because it's a foreign government in a failed state that's a basketcase at this stage.

>> It's not going to be an easy ride.

>> DORNSTEIN: Right.

You and I can't do what we did a few years ago in today's Libya, can we?

>> Uh-uh.

You know the bombings and political unrest and all of this terrorism that's happening, and, you know, the power vacuum, all of these militias, the carjackings.

You know, there's an ongoing war now in Libya.

>> Libya has descended into its worst violence since the uprising that ousted Moammar Qaddafi three years ago.

Dozens of civilians are caught in the crossfire between Libyan special forces and Islamist militants.

>> The country is in chaos.

U.S. diplomats are gone from the embassy and Islamic militants are there celebrating.

>> Plunging into the pool at a U.S. embassy in Tripoli.

The acrobatics a celebration... >> DORNSTEIN: The news from Libya was consistently grim.

Some people I talked to there quietly longed for the order of the old regime.

>> In Libya, a trial has begun for the sons of Moammar Qaddafi and more than two dozen of his ex-officials.

>> DORNSTEIN: At the same time, in Tripoli, the new government was continuing its trial of former Qaddafi officials.

>> The ex-spy chief, Abdullah al Senussi, was among the defendants fenced off behind bars.

>> From corruption to war crimes related to the 2011 uprising... >> DORNSTEIN: The Libyans were interested in crimes committed during the revolution, but I was listening at home for details about the men on my list.

Then, in the middle of the trial, a photo arrived by email from Musbah Eter.

It was poor quality and came with no explanation.

But, in the center of the frame, was a dark-skinned man.

The blue jumpsuit and prison bars made it pretty clear that he was was one of the men on trial in Tripoli.

So I went looking for every photo I could find of these men on trial.

And, there, in one of them-- behind Abdullah Senussi, the former intelligence chief-- was the dark-skinned man.

The more I looked, the more photos I found of him.

I captured these images and sent them to Musbah Eter in Berlin.

He said this was indeed the bomb expert, Abu Agela, 100%.

It was hard to believe I was now looking at the man I'd been trying to find for so many years.

But I still wanted more confirmation.

So I connected with a human rights worker who'd been monitoring the trials in Libya.

>> Hi, Ken.

>> DORNSTEIN: Hey, how are you?

>> We can attempt cameras, but I'm not sure it's gonna last.

>> DORNSTEIN: I told her who I was looking for.

At first, she couldn't find Abu Agela's name on the list, but then... >> Wait, wait, wait.

I have a name.

It's just written slightly differently.

>> DORNSTEIN: What does it look like to you?

>> I think it's defendant number 28 in this case.

So his first name is Abu A'ujilah.

That would be his first name.

And, to my understanding, the biggest case against him seems to be bomb making in relation to the 2011 conflict.

Charges of setting up bombs in vehicles.

>> DORNSTEIN: Wow.

Well, that sounds like him.

>> Yeah.

I would say that's for sure the same person.

>> DORNSTEIN: The main trial of these guys, there's 36, 37 of them, and they're there for what is more or less a show trial.

>> Right.

>> DORNSTEIN: That's Abdullah Senussi.

But if you look behind Abdullah Senussi... >> There's a dark-skinned man.

>> DORNSTEIN: There's a dark-skinned man.

You pull all the images, and you keep finding a dark-skinned man.

>> Right.

>> DORNSTEIN: But I still would like to know more.

So, I said, "There's 36 men on trial.

Is there a charge sheet here?"

>> Yeah, what are they charged with?

>> DORNSTEIN: Number 28 on the charge sheet.

And I translate it, and you can even grab it, and put it into Google Translate, and it's "A'bujilah Masoud."

And the charge is bomb making.

>> My goodness.

From a moral standpoint, and from an administration of justice standpoint, I can see no good reason not to pursue this.

That's not to say you're not gonna run into a brick wall.

>> DORNSTEIN: I'm interested in the story that connects La Belle, Lockerbie... >> So I'm mainly responsible for collecting evidence.

>> DORNSTEIN: Well, that's really what I'm interested in.

I made contact with a German lawyer who had extensive files on Libyan terror operations.

I'm deeply interested in all the nitty gritty of who did what, and there's one person whose name comes up.

>> What's his name?

>> DORNSTEIN: Massud Abu Agela.

>> Yeah, yeah.

We were checking the files, but we haven't found anything on this name.

So what I would suggest is that we meet each other.

>> DORNSTEIN: The lawyer was willing to help me track the bomb expert, Abu Agela, who, he said, was still wanted for the disco bombing.

The lawyer was also interested in the link to Lockerbie.

In both cases, the key witness would turn out to be the lawyer's client, Musbah Eter.

Since my last trip to Berlin, I learned the U.S. government had contacted Eter.

They'd apparently heard about the link I'd found between him, the Libyan bomb expert, and Lockerbie.

>> I believe the law enforcement people, they are motivated and take it for serious.

>> DORNSTEIN: Andreas Schulz is Musbah Eter's lawyer.

He was careful not to reveal too many details of the ongoing investigation.

>> Well, the competent authority in the U.S. is the F.B.I.

for this case.

And that means the F.B.I.

was here.

>> DORNSTEIN: About Lockerbie?

>> Recently, yes.

But the main problem is time.

Time is running against the investigation, because these people are at a certain age.

But, you know, this is in the hands of the U.S. authorities.

If you put all the power and capability the U.S. has, I think there are always ways to get their hand on the culprits of Lockerbie.

So it's a question of the political will.

>> DORNSTEIN: Since the bombing in 1988, the F.B.I.

has maintained Lockerbie as an open case.

But, to my knowledge, they never found a witness with real firsthand information about the plot.

That is, until they apparently became aware of my reporting about Musbah Eter, then requested to meet with him several times at the U.S. embassy in Berlin.

It was in these meetings, I later found out, that Eter offered new details about Lockerbie.

Eter told the F.B.I.

that he had no doubt that Lockerbie was carried out by Libyan intelligence.

He said the operation was led by Said Rashid, who spoke often about the need to avenge the U.S. bombing of Tripoli with at least double the casualties.

During the year before Lockerbie, Eter said, Rashid hatched a plan to take down a U.S. plane.

He said Abdel Baset al Megrahi was part of these early discussions, and would be a key member of the team that would carry it out.

Most significantly, Eter said he had conversations with the technical expert who he'd worked with on the disco bombing, Abu Agela.

And that Abu Agela personally told him that he'd helped carry out Lockerbie.

Abu Agela apparently also took responsibility for La Belle and the bombing of a French passenger plane that killed 170 people.

>> If he's said these things, and there are facts to back up some of the things he says, and it sounds like there are, I don't know why they would not want to bring that to court.

>> DORNSTEIN: Right.

>> If there's somebody alive today that was involved in this, and there's knowledge of that, we should be going after them.

We should be going after them.

We would have gone after them in 1991, if... especially if we had this kind of information.

We would have indicted, certainly would have indicted him.

>> DORNSTEIN: When it came to Abu Agela, the original Lockerbie investigators did gather important evidence that they were never able to use against him.

This evidence centered around the airport in Malta, just off the Libyan coast, where the bomb was said to have originated.

Here they found the landing card that showed Abu Agela had entered Malta the week before the bombing, complete with the passport number that matched the C.I.A.

and Stasi records.

They even had Abu Agela's fingerprints.

Then they found the passenger list for the flight that Abu Agela took home to Tripoli the day of the bombing, possibly after helping arm the device that was then sent onto Flight 103.

Joining Abu Agela on that flight was Abdel Baset al Megrahi, who was traveling under a known alias.

All of this evidence was gathered years ago, but it took Musbah Eter's statements in Berlin to apparently tie it all together and potentially generate the first new charges in the case in some 25 years.

>> The more we go deeper into this, the more we realize we were always on the right track.

We were always right about this.

>> DORNSTEIN: Right.

>> How does that make you feel like... where are we now?

>> DORNSTEIN: I don't know.

It's gone about as far as I can go.

What happened inside that embassy, that's out of my hands and Eter's now potentially a witness in a federal case.

He's not a guy in my movie anymore.

>> I think you've pushed as hard as you can push.

Maybe this is as far as you can go, so... >> DORNSTEIN: The whole purpose of finding them was to come face to face, sit there with someone and say, "You know you killed my brother, "and he was a real person, and I loved him and other people loved him."

>> Yeah.

>> DORNSTEIN: "And you shouldn't have done that."

>> Yeah.

Terrorists killed your brother and my friend.

I don't know that we can cause them to feel accountable or to feel shame for what it is that they produced.

They ended his life and there were maybe 270 other David Dornsteins who were aboard that particular flight and we're not going to bring those people back.

>> I think about him constantly.

I think about what was lost when he was lost and how lucky I was to have known David Dornstein.

I mean, there are all sorts of ways to pursue meaning from tragedy.

And killing David on that plane, the only way that I can make sense of it is...

I can't make sense of it.

>> DORNSTEIN: I'm sure there are people in my life who are thinking, "It's not healthy for you "to go on chasing Libyans, "chasing some kind of truth that won't bring your brother back, and doesn't allow you to live your life fully."

>> Do you go on?

That's what you're asking.

Do I go on?

I think only if you can rein it in sufficiently not to allow it to destroy your existing family and your future family and your future happiness, because you can't bring back the people you lost.

>> DORNSTEIN: Right.

I've done everything I could...

These days, Dr. Jim Swire still maintains his campaign for a new inquiry into the bombing.

He still believes that much of the prosecution case against Megrahi and the Libyans doesn't hold up to scrutiny.

I want you to see the things that you might not be aware of that raise questions for me.

What I found is that...

I walked Dr. Swire through the trail of papers that led me to the man I believed to be the Lockerbie bomb expert.

Abu Agela Mas'ud.

And I tried to explain how this bomb expert-- Abu Agela Mas'ud-- was tied to the man whose innocence Dr. Swire had been fighting for over the years.

So, Megrahi is traveling with this person Abu Agela Mas'ud before the bombing, and it's hard for me to imagine Megrahi himself wasn't involved.

>> Mm-hmm.

>> DORNSTEIN: This person is a known bomb expert traveling with Megrahi the day of Lockerbie.

>> Mmm.

>> DORNSTEIN: If this story that I'm putting together here were true, it would challenge a lot of what you have come to believe.

>> Mmm.

I don't know what to make of that.

But, on the other hand, I'm not the sort of guy who wants to sit around and watch this sort of thing dismissed as not worth pursuing simply because it doesn't match what we think we know.

But you've got to take it to the next step, I'm afraid.

Great to see you.

>> DORNSTEIN: Thank you.

Terrific.

Over the course of the year after this meeting, Dr. Swire continued to fight against the original verdict in the Lockerbie case.

And I continued to develop evidence about the Libyan bomb expert, Abu Agela.

As I gathered more information, I shared it all with Dr. Swire and he always responded in a very thoughtful way.

In the end, he allowed that Abu Agela and others in the Qaddafi inner circle may have played a role in Lockerbie, but he remained wholly committed to one core belief: that his friend Abdel Baset al Megrahi was innocent.

Megrahi himself was now dead, of course.

And so was the likely mastermind of the bombing, Said Rashid.

And Abdullah Senussi?

The former intelligence chief has been on trial in Tripoli.

And in the summer of 2015, he was finally sentenced.

>> Abdullah Mohammed Senussi.

>> In news from Libya, the former head of intelligence and eight others have been sentenced to death for committing war crimes during the crackdown against... >> DORNSTEIN: Abu Agela was sentenced as well.

He was given ten years for making bombs during the Libyan Revolution.

But thus far, he faces no charges for his possible role in Lockerbie.

>> I mean, the issue of Lockerbie, the biggest victim is the truth.

The simple truth.

Forget about indictments, about who goes to jail.

It's the simple truth of what happened.

Why.

Because nobody has a stake in telling you the truth.

>> DORNSTEIN: The F.B.I.

and the Justice Department say they can't comment publicly about the Lockerbie case, which remains an ongoing investigation.

And though it's been some 25 years since they last filed charges in the case, they maintain that they've been "working aggressively "to bring those responsible for the bombing of Pan Am Flight 103 to justice."

>> I think that David would be proud of you for both keeping his memory alive but also by doing something that is very much in the spirit of what David would have done had he been in your shoes.

I hope that when this project is done, you will close this chapter and move on with your life and keep David's memory alive, particularly by communicating all of the best things about him to your children.

>> Go to pbs.org/frontline and explore an interactive guide to filmmaker Ken Dornstein's investigation.

>> I kept coming back to those images I'd gotten out of state TV in Libya.

>> Hear more from Ken about his brother in a special podcast.

>> I was the keeper of every ambition that he had.

>> Learn more about the ongoing unrest in Libya.

>> There's no justice to be had.

>> Watch all three episodes of "My Brother's Bomber," or listen to audio versions of the series.

Connect to the Frontline community on Facebook and Twitter.

And sign up for our newsletter at pbs.org/frontline.

>> Tonight, I'd like to talk with you about immigration.

>> Inside the halls and inner offices of Congress.

>> Ain't nobody fell in love with immigrants yesterday.

>> The fight over immigration.

>> How do you make it self-enforcing so it doesn't depend on the whim of any president?

>> And how Washington really works.

>> I expect some House Democratic types to try to shut it down.

>> Congress talked, but doesn't act.

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