MADISON, Wis. (AP) — Wisconsin Assembly Speaker Robin Vos on June 7 challenged signatures on petitions filed seeking an election to recall him from office, saying there were not enough valid ones.

The bipartisan Wisconsin Elections Commission has until June 28 to determine whether there are enough valid signatures to trigger a recall election. The panel rejected the first attempt for not having enough.

Vos is being targeted by supporters of former President Donald Trump, including former Wisconsin Supreme Court Justice Michael Gableman, who submitted more than 9,000 signatures May 28.

They targeted Vos, the longest-serving Assembly speaker in Wisconsin history, after he refused to impeach the official who oversees the battleground state’s elections, angering Trump and his followers.

Vos said June 7 he found thousands of invalid signatures, including 2,000 collected from outside his current legislative district, more than 400 who signed more than once and nearly 350 that were collected beyond the allowable window.

Vos also alleged that signatures were gathered at addresses that didn’t exist, were vacant, or were not residences.

Earlier on June 7, those who circulated the petitions insisted that they had enough valid ones to trigger the recall. They need 6,850 valid signatures to force a recall election in the district where Vos was elected to serve.

In March, the group submitted more than 9,000 signatures, but the elections commission determined that only 5,905 of them were valid.

Vos angered Trump and those who falsely believe the former president won Wisconsin in 2020 when Vos refused calls to decertify President Joe Biden’s narrow win in the state. Biden’s win of about 21,000 votes has withstood two partial recounts, numerous lawsuits, an independent audit and a review by a conservative law firm.

Vos further angered Trump supporters when he did not back a plan to impeach Meagan Wolfe, the state’s top elections official.

The recall is complicated because new legislative maps go into effect in the fall election.

The elections commission asked the Wisconsin Supreme Court to clarify whether any recall election should take place in the district where Vos was elected to serve, or under new district boundary lines that take effect for the regular November election.

The court declined to further clarify or amend its December ruling that found the current maps to be unconstitutional and barred their future use.