Islamic State (ISIS) militants on Monday night staged their second prison riot in 24 hours at the holding facility in Hasakah, a city in northeastern Syria controlled by Kurdish forces.

Kurdish officials said they narrowly avoided a “catastrophe” and warned they are having increasing difficulty controlling the ISIS prison population.

Kurdish news service Rudaw reported shots were fired at the prison and ambulances were seen ferrying the wounded to area hospitals. As many as 5,000 militants are incarcerated in the Hasakah prison, including ISIS recruits from 50 different countries.

“U.S.-led forces were spotted overhead dropping flares to illuminate the area and aid the Kurdish forces in their attempt to get the situation under control,” a local citizen journalist reported.

According to a report at Military Times, U.S. aerial surveillance units are on station around the prison, supplying intelligence to the Syrian Democratic Forces (SDF).

There is evidently some disagreement about if any prisoners escaped, and how much of the prison has been brought back under control:

While the Kurdish led-SDF force commander Mazloum Abdi has assured the international community that “no prisoners escaped,” the Syrian Observatory for Human Rights (SOHR) claimed that four militants escaped the facility during the initial riot. The head of the prison confirmed to Rudaw on Monday that ISIS militants are still in control of the ground floor. “Now, the ground floor of the prison is in the hands of the brigands so we cannot break into that floor,” Rubar Hassan told Rudaw, referring to ISIS militants. He added that the prisoners “smashed all the CCTV cameras and the internal doors.” The ISIS “members are still out of control on one of the floors,” SDF official Mervan Qamishlo confirmed to AP [the Associated Press]. According to Rudaw’s Rangin Sharo, SDF counterterror forces have arrived at the scene, cordoning off the area to prevent any possible escape.

Mazloum Abdi, a commander in the Kurdish-led SDF, said the riots bring new urgency to the SDF’s warnings that it cannot contain huge numbers of ISIS prisoners without outside assistance — ideally including foreign governments repatriating citizens who defected to ISIS, a step few countries have been eager to take. The SDF estimates it is holding about 12,000 ISIS fighters plus 100,000 of their wives and children.

“Our allies must find a quick radical solution to this international problem,” Abdi said.

The U.K. Guardian noted a video clip from inside the prison that suggested coronavirus fears might have played a role in sparking the riot:

In security camera footage broadcast by the Kurdish news agency ANF, men in orange jumpsuits in a crowded room held a banner up to the camera demanding their human rights be respected. It was not immediately clear whether the riot was linked to fears over a potential coronavirus outbreak.

CNN correspondents reported hearing “loud chanting from prisoners” inside the building, although they did not specify what was being chanted. The CNN report insisted some prisoners did escape during the riot, but it didn’t say how many or identify any of the escapees.

Various reports suggest the riots have inflicted considerable damage on the prison, including cell doors removed and holes knocked in the walls, which could make it difficult to get the facility fully up and running again.