At least 45 people, including rebel fighters and members of their families, were killed in overnight Russian airstrikes in Syria's coastal mountains, a monitoring group said on Tuesday.
Another 75 people were injured in the raids on the Jabal al-Akrad area, near the mountain front lines between government forces and rebels, the Syrian Observatory for Human Rights reported.
Among those killed was the commander of the First Coastal Division, a moderate rebel group that has reportedly received arms supplies from the United States, the Observatory said.
Syria's coastal plain and the mountain range just inland from it are a stronghold of President Bashar al-Assad's Alawite sect, and are mostly under government control.
The Jabal al-Akrad area in the north of the mountain range, however, is held by rebels.
The area has seen fierce battles over the past two weeks. It is the furthest point west on a 130-kilometre long front line where government forces, backed by Russian airstrikes, are trying to win back territory lost to the opposition, so far with limited results.
Russia has said its intervention is targeting Islamic State (Daesh) and other extremist groups, but more moderate groups backed by the US, Turkey and Gulf states have been hard hit.
By Weedah Hamzah
