The Lebanese army announced that a ceasefire in its own offensive took effect at 7:00 a.m (12 a.m. ET) but did not mention Syria's side of the frontier, as reported by Reuters.

Read alsoCourt arrests ISIL 'commander' in central Turkey – mediaHezbollah and the Syrian army declared a ceasefire in their attack against Islamic State in Syria's western Qalamoun region, Hezbollah's al-Manar TV said.

The Lebanese army said the ceasefire would pave the way for negotiations over the fate of the soldiers.