The US has carried out air strikes against Iran-linked groups in eastern Syria after a drone attack killed a US contractor, the US defence chief said. Eight pro-Iran fighters were killed, according to a monitoring group. Defence officials said the air strikes happened on Thursday night, hours after the drone attack which US intelligence said was "of Iranian origin". US bases in north-east Syria have come under attack before, with the US responding with air strikes. สอนเล่นบาคาร่า