Hundreds of civilians are fleeing two cities held by ISIS in eastern Syria after a series of deadly airstrikes that killed dozens, activists said Saturday.
The Syrian Observatory for Human Rights, a Britain-based activist group, said a "large-scale displacement" was underway from the cities of Albu Kamal and Mayadeen.
"Hundreds of civilians are fleeing the two cities heading towards villages in the countryside," the Observatory said.
The activist group's director, Rami Abdel Rahman, said civilians had begun fleeing Friday but that the displacement was continuing Saturday morning.
He said relatives of ISIS fighters were among those fleeing.
The two cities are in Syria's oil-rich eastern Deir Ezzor province, which is largely under the control of ISIS and regularly targeted by the U.S.-led coalition, as well as Syria's regime and its ally Russia.
On Friday, at least 80 relatives of ISIS fighters were killed in U.S.-led coalition bombing of Mayadeen, according to the Observatory.
Air raids by the coalition have pounded ISIS positions across Iraq and Syria since the extremist group claimed responsibility for the devastating bombing at a concert in the English city of Manchester Monday.
Activists said 33 children were among the dead in the strike on Mayadeen Friday, the third day of heavy bombardment of the town.
According to the Observatory, 37 civilians were killed in coalition raids on the town Thursday night, including 13 children, and another 15 were killed in coalition strikes Wednesday.
Mayadeen has seen an influx of displaced families from ISIS-held territory in Iraq and Syria, including its bastion Raqa.
Albu Kamal sits on the border between Iraq and Syria and has also regularly been targeted in airstrikes.
Earlier this month, at least 62 people, including 42 civilians, were killed in strikes on the town.
The U.S.-led coalition denied responsibility for those strikes.
On Thursday, a Pentagon investigation concluded that at least 105 civilians died in an anti-extremist airstrike on an ISIS weapons cache in Mosul in March.
Before the new revelation, the U.S. military had said coalition airstrikes in Iraq and Syria had "unintentionally" killed 352 civilians since 2014.
But activists say the true number is much higher