Syrian government warplanes bombed Kurdish-held areas of the northeastern city of Hassakeh on Thursday for the first time in the country's five-year-old civil war, killing at least 13 people, the Syrian Kurdish YPG militia and a monitoring group said.
The powerful YPG, a crucial partner in the U.S.-led war against Islamic State, said it would "not be silent" over what it called it an act of flagrant aggression. There was no immediate comment from the Syrian government.
People's Protection Units (YPG) spokesman Redur Xelil said the airstrikes had hit Kurdish districts of the city, which is mostly controlled by Kurdish groups, and positions held by a Kurdish security force known as the Asayish.