BEIRUT - Syrian opposition activists and a war monitoring group say rebels have launched an offensive in the mountains of the coastal Latakia province, overrunning a series of Syrian army positions.

The Syrian Observatory for Human Rights says clashes are underway in several locations in the Turkman Mountains. It says the fighting killed 35 people on both sides in the opening hours. There was no immediate government comment.

Several opposition activists also reported Tuesday’s operation.

Syria is locked in a devastating civil war pitting President Bashar Assad’s forces against rebels seeking to topple him. The new rebel assault comes as Assad’s troops are on the offensive in the nearby Idlib province, the last major area held by opposition forces in Syria.