Syrian shells struck a Turkish observation post at Taftanaz airbase in the opposition-held part of Idlib province of northwest Syria on Monday, killing 5 Turkish soldiers and injuring five others. Syria government forces are in the middle of a major offensive to recapture the last province remaining in rebel hands. It is supported by Iran-backed militias and Russian air strikes. A week ago, 8 Turkish troops were killed in a similar artillery attack amid the Syrian push into Idlib. Ankara, which backs the rebels, has given Damascus up to the end of the month to pull back to former ceasefire lines.