Fresh airstrikes in Syria’s Idlib kill 12 civilians

At least 12 civilians were killed by airstrikes in Syria's opposition-held Idlib province on Friday.

Warplanes targeted a number of towns and villages, bringing the total civilian death toll in the northwestern province to 35 within the last four days, according to a tally by Anadolu Agency.

On Thursday, the U.S. State Department voiced its concern over the recent series of airstrikes in both Idlib and Hama province, which, it said, had killed medical personnel and damaged a number of medical facilities.

"These attacks fit an all-too-familiar pattern in which medical facilities and personnel -- and the civilians they serve -- are victims of strikes by the Syrian regime and its Russian allies," the State Department said a statement.

Despite Washington's assertions, however, it remains unclear what states or groups have been responsible for the deadly airstrikes.

Syria has been locked in a vicious civil war since 2011, when the Assad regime cracked down on pro-democracy protests with unexpected ferocity. Since then, hundreds of thousands of people have been killed in the conflict, according to UN figures.