This story has been updated.

A Syrian militia said no alleged Islamic State prisoners had escaped, contrary to initial reports, after the group quelled a prison uprising with the help of aircraft from U.S.-led coalition forces.

The U.S.-backed Syrian Democratic Forces, which operate the prison in the northeastern Syrian town of Hassakeh, sent counterterrorism forces and reinforcements to put down the riot and secure the facility late Sunday, said Kino Gabriel, a spokesman for the Kurdish-led militia group.

“ISIS terrorists managed to sabotage and remove the internal doors of the cells, create holes in the dormitory walls, and control the ground floor of the prison,” Gabriel said in a statement Monday. “We confirm that there are no escape incidents of the detainees, and that the situation in the detention center is completely under control.”

Earlier, SDF members searched for prisoners thought to have escaped, said Mustafa Bali, another spokesman for the group, in a Twitter post shortly after the riots began.

Four prisoners were caught at the facility’s perimeter with the help of surveillance aircraft from the U.S.-led coalition, the London-based Syrian Observatory for Human Rights reported, citing sources on the ground.

Overnight, there was “heavy overflight” of coalition warplanes, reported the Rojava Information Center, a Syria-based collective of researchers and journalists. On Monday afternoon, the coalition was “back to normal ops,” Army Col. Myles B. Caggins III, the anti-ISIS coalition’s military spokesman, told Stars and Stripes in a text message.

The attempted prison break started after inmates held up blankets with messages to the U.S.-led coalition and human rights organizations scrawled on them, Rojava said on Twitter, citing an official statement. Counterterrorism forces stormed the building Monday after waiting until daybreak, the center later reported.

The fact that the rioters wrote messages to human rights organizations suggested the unrest may have been linked to concerns over prison conditions and fears of the coronavirus pandemic, the center said. The prison is located in an area where Turkish-backed militias are accused of cutting off the water supply to more than 450,000 people for more than a week.

The coalition does not staff the prisons in northeast Syria, which have struggled to detain the roughly 10,000 ISIS-linked captives. The SDF does not have the capacity to investigate them and give them trials, and European countries have been reluctant to take back their share of the roughly 2,000 foreign recruits held in the facilities.

Camps in the region also hold tens of thousands of women and children who lived under the terrorist group’s “caliphate,” which lost its final territorial stronghold a little more than a year ago in the town of Baghouz.

As Turkey invaded northern Syria last fall and President Donald Trump ordered the withdrawal of U.S. forces from the border region, the Kurds warned that they would not have the capacity to both defend themselves and secure the prisons. Prison guards left their posts to fight on the front lines in October, and more than 100 prisoners with alleged ISIS ties reportedly escaped.

“The longer ISIS prisoners are held in SDF prisons, the greater the potential for them to organize breakouts,” the Lead Inspector General for Operation Inherent Resolve said in a January report, citing Pentagon officials.

ISIS leaders have repeatedly called on its supporters to attack the detention camps and free the prisoners. The group‘s ranks have been filled by fighters freed in prison breaks stretching back more than a half-decade, the Washington Post reported.

The U.S.-backed Kurdish militia’s suppression of Sunday night’s riots “confirm the ability of the SDF to secure ISIS terrorists,” Gabriel said, but he called for more support from the international community “in order to provide maximum protection to detention centers and camps that contain ISIS terrorists and their family members.”

Despite losing its territorial control, the group continues to fight an insurgency in both Iraq and Syria.

The attempted prison break Sunday came as the coalition pulled out of a third Iraqi base in a month. Officials have cited success against the terrorist group for enabling the withdrawal.

On Monday, the coalition handed over its compound at a fourth base, the Nineveh Operations Command in Mosul, the Iraqi military said online. The city, formerly ISIS’s Iraqi capital, was liberated from the terrorists in the summer of 2017.

garland.chad@stripes.com

Twitter: @chadgarland

