At least 23 ISIS militants were killed in continuing clashes sparked by an extremist attack on a Kurdish-run prison in north-eastern Syria, according to a military source from the Kurdish-led Syrian Democratic Forces.
Seven members of the US-backed SDF forces were also killed in the ISIS attack on the prison in Hassakeh, according to the source.
The rare attack on Ghwayran prison in Hassakeh province on Thursday saw the extremists detonate a car bomb near the jail and attack Kurdish forces guarding the facility in an attempt to free some of the group's members, the SDF said.
The Syrian Observatory for Human Rights monitor said “five ISIS prisoners managed to break out”, but it remains unclear whether they have since been killed or recaptured.
The US-led coalition battling ISIS said “SDF casualties ensued during the attack”, but it did not disclose how many.
The assault triggered clashes between the extremists and SDF forces around the prison that continued into Friday amid heightened security measures, the Observatory said.
“Clashes are ongoing between ISIS fighters and [Kurdish] military forces in the area,” Observatory director Rami Abdel Rahman told AFP, describing it as one of the largest such attacks by ISIS since its proto-state was declared defeated in 2019.
“At least six ISIS fighters have been killed in the clashes,” Mr Abdel Rahman said, without specifying casualties among Kurdish security forces.
The SDF, which oversees the jail, said on Friday that it “arrested two ISIS fighters that tried to escape from the Ghwayran prison” as part of combing operations following the attack.
The extremists were captured in the vicinity of the jail, it said.
It said ISIS militants that carried out the attack were hiding in civilian homes in the neighbourhood of Al Zuhoor near the jail.
“Exceptional security measures in the vicinity of the prison and surrounding neighbourhoods are ongoing,” it said in a statement on Friday morning.
ISIS fighters “are using civilians in the Al Zuhoor neighbourhood and areas north of the prison as human shields,” it said, adding that ISIS had killed some civilians in the area.
“Our forces and the relevant security services are moving with great precision and sensitivity to contain this incident.”
Ghwayran is one of the largest facilities housing ISIS fighters in a semi-autonomous region controlled by Kurdish authorities in north-east Syria.
According to Kurdish authorities, more than 50 nationalities are represented in a number of Kurdish-run prisons where more than 12,000 ISIS suspects are now held.