BEIRUT (AP) -- U.S.-backed Kurdish-led fighters searched Friday near a Syrian prison for Islamic State group militants and gave an ultimatum to dozens of armed extremists holed up in a small part of the jail to surrender or face an all-out attack, a Kurdish official said.
About a half-dozen IS fighters surrendered Friday morning, among scores of militants hiding in a basement in the northern section of the prison, according to Siamand Ali, a spokesman for the U.S.-backed Syrian Democratic Forces.
He would not confirm or deny a report by the Britain-based Syrian Observatory for Human Rights, an opposition war monitor, that SDF fighters discovered the bodies of 18 of their comrades inside Gweiran prison, also known as al-Sinaa prison, in northeast Syria on Friday.
The Islamic State group's Jan. 20 attack on the prison was the biggest military operation by the extremist group since the fall of their self-declared caliphate in 2019. It came as the militants staged deadly attacks in both Syria and Iraq that stoked fears that IS may be staging a comeback.
The weeklong assault on one of the largest detention facilities in Syria has turned the city of Hassakeh into a conflict zone. The Kurdish-led administration declared a curfew and sealed off the city, barring movement in and out.
Thousands of people in Hassakeh were displaced in recent days because of the fighting.
The SDF claimed Wednesday it had regained full control of the prison -- a week after scores of militants overran the facility. The attackers allowed some to escape but also took hostages, including child detainees, and clashed with SDF fighters in violence that killed dozens.
The SDF had said that between 60 and 90 militants were hiding out in the northern section of the prison.
Ali said the militants are in the basement of a two-story building and that those who remain inside are refusing to surrender. "Our units are surrounding the building and are trying to convince them to surrender," he said.
"We gave them a deadline and we are besieging them," Ali said by telephone from Hassakeh. He refused to say when the ultimatum ends and the attack begins, for security reasons.
The Observatory said SDF fighters are betting that more time will force IS militants to surrender as their food dwindles.
The Hawar News Agency, ANHA, an online Kurdish news service, reported that several automatic rifles, a rocket-propelled grenade and hand grenades were confiscated from the IS gunmen who surrendered Friday. It added that SDF fighters are conducting search operations in the prison as well as several Hassakeh neighborhoods in search for IS sleeper cells.
The SDF said about 3,000 inmates have surrendered since its operation to retake the prison's northern wing began three days ago.
At least 300 foreign child detainees are believed to be held in the Gweiran facility. Thousands more, mostly under the age of 12, are held with their mothers in locked camps in other parts of northeastern Syria on suspicion of being families of IS members. Most countries have refused to repatriate them, with only 25 out of 60 countries taking back their children, some without their mothers.
The Britain-based Observatory put the death toll from the struggle at over 260, including over 180 militants and more than 73 fighters from the Kurdish-led force. At least seven civilians were killed in the fighting, the Observatory said. The SDF said preliminary information put the force's death toll at 35.