A bomb blast at a border crossing between Syria’s opposition-held Idlib province and Turkey killed at least 10 Syrian rebel fighters on Sunday, activists said, as a wave of airstrikes pounded the region and fighting raged in the contested northern city of Aleppo.

The Britain-based Syrian Observatory for Human Rights said a suicide bomber struck a bus transporting fighters through the Atmeh border post, one of several crossings Syrian rebels use to bring in fighters and supplies. The monitoring group, which relies on activists inside Syria, said the attack killed 10 fighters. Continue reading.