BEIRUT - Lebanon's army announced a ceasefire on Sunday in its offensive against Islamic State militants at the northeast border with Syria.

The ceasefire takes effect at 7:00 a.m. (0400 GMT) to pave the way for negotiations over the fate of Lebanese soldiers who are in Islamic State captivity, the military statement said.

Northeast Lebanon saw one of the worst spillovers of Syria’s war into Lebanon in 2014, when Islamic State and other militants briefly overran the border town of Arsal. The fate of nine soldiers that Islamic State took captive then remains unknown.

The Lebanese army has been fighting Islamic State militants in their last border foothold, near the town of Ras Baalbeck.

The attack began last week, coinciding with an offensive that Hezbollah and the Syrian army launched against Islamic State on the other side of the frontier in Syria’s western Qalamoun region.