Fighters identified as Islamist militants crossed into Lebanon from Syria on Saturday, triggering an exchange of fire with Lebanese villagers who forced them back across the border, Lebanese security sources and a villager said, Alarabiya reported.
The gun battle near the village of Kfar Qouq followed a battle between gunmen and Syrian security forces on the other side of frontier, the sources said. It was not immediately clear if there were any casualties.
Kfar Qouq is near the Bekaa Valley town of Rashaya and some 100 km south of the border town of Arsal that was seized last Saturday by Islamist militants who crossed from Syria. That incursion was the most serious spillover yet of Syria's three-year-long civil war into Lebanon.
Dozens of people were killed in five days of fighting between the army and the militants who included Islamists affiliated to the Islamic State of Iraq and Syria (ISIS).
The militants pulled out of Arsal to the mountainous border zone on Thursday, taking with them 19 captive soldiers. Militant sources told Reuters on Friday they sought to exchange them for Islamists held in Lebanese jails.