A staff member at Wisconsin’s youth prison was in critical condition on June 25 following a fight with an inmate, state Department of Corrections officials said.

The fight happened on the evening of June 24 at the Lincoln Hills-Copper Lake Schools, the state’s youth prison in Irma in northern Wisconsin. Department of Corrections spokesperson Beth Hardtke said a 16-year-old inmate assaulted a staff member in a residence hall and then attacked a second staff member.

The first staff member was taken to a hospital, treated and released. The second staff member’s head struck concrete, however. The worker was taken to a hospital and remained in critical condition on the morning of June 26, Hardtke said.

The inmate did not suffer any injuries that required medical treatment, she said. The Corrections Department was working June 26 to move that inmate to a “suitable facility.” She did not say where and did not immediately respond to follow-up emails asking where the inmate would go and for more details about the two staff members’ positions.

Lincoln Hills-Copper Lake is Wisconsin’s only youth prison. The facility has been plagued by allegations of staff-on-inmate abuse, including excessive use of pepper spray, restraints and strip searches. A court-appointed monitor is currently overseeing the facility.