The Syrian Observatory for Human Rights, a British-based monitoring group, said on Thursday that at least 38 civilians were killed in airstrikes carried out by a U.S.-led coalition in Hasaka province in northeast Syria in the past two days.
The United States and its allies are carrying out air raids in the area against Islamic State, which controls some parts of Hasaka province but has lost ground in recent months.
Hasaka borders mostly Islamic State-held Deir al-Zor province and Raqqa, the group's de facto capital in Syria.