A video released by government-controlled Syrian Central Military Media (SCMM) on Monday showed Hezbollah fighters backed by the Syrian army fighting al-Qaida-linked militants along the Syrian-Lebanese border.

SCMM said on Sunday a faction fighting alongside the al-Nusra Front announced a ceasefire arranged with Hezbollah.

Pro-Hezbollah activists said on social media that some 15 Lebanese fighters had been killed in the first two days of fighting.

The offensive was widely expected after negotiations with militants to leave the area failed over the past days.

Hezbollah has been in Syria's civil war since 2013 backing President Bashar Assad's forces.

(Source: AP)