Islamic State (IS) inmates staged a riot at a prison run by the Kurdish-led Syrian Democratic Forces (SDF) in Hasakah province, a war monitor reported.
The riot broke out on Monday in the Ghweiran prison, demanding “fair trials” and allowing visits by their families, Xinhua news agency quoted the UK-based Syrian Observatory for Human Rights as saying.
The watchdog group said the IS inmates tried to destroy the walls and gates of the prison amid confirmed information of casualties among the prisoners.
In tandem with the riot, helicopters of the US-led anti-terror coalition flew on a low altitude in Hasakah.
The IS prisoners staged a similar riot on May 3, which ended after hours of negotiations between the inmates and the US-backed SDF.
The SDF runs prisons in areas it controls in northeastern Syria, where around 10,000 IS members are imprisoned, 2,000 of whom are foreigners.
The North Press Agency, a media outlet running in Kurdish areas in northeastern Syria, said dozens of SDF members arrived in the vicinity of the prison in Hasakah on Monday.
It added that the SDF closed the roads leading to the prison.