An all-out assault is said to be underway to drive Sunni militants from their last stronghold along the Syria-Lebanon border.
Fighters from Lebanon’s Shi’ite militia Hezbollah, backed by the Syrian army, are targeting insurgents from the former al-Nusra Front, which used to be allied with al-Qaeda.
The Sunni militants have been in control of a mountainous area around Juroud Arsal.
Hezbollah says its forces have recaptured several strategic points and border crossings.
Since the new offensive began on Friday more than 60 fighters are reported to have been killed, with the majority of the deaths among the Sunni insurgents.