Syrian regime captures 14 villages from rebels in Idlib offensive
The main aim of regime forces is to reach the rebel-held Abu Zuhour airbase and secure the road linking the capital, Damascus, with the northern city of Aleppo.
Rebels captured Abu Zuhour in 2015 after a three-year siege.
The military offensive in southern areas of the Idlib province comes amid intense airstrikes and shelling that have killed more than 21 civilians - including eight children and 11 members of the same family
The Syrian conflict began when the Baath regime, in power since 1963 and led by Assad, responded with military force to peaceful protests demanding democratic reforms during the Arab Spring wave of uprisings, triggering an armed rebellion fuelled by mass defections from the Syrian army.
The brutal tactics pursued mainly by the regime, which have included the use of chemical weapons, sieges, mass executions and torture against civilians have led to war crimes investigations.