Syrian troops have closed a border crossing into Lebanon amid heavy clashes with rebels in the area, according to Lebanese media.
The state-run National News Agency said the fighting around the Bqaiaa crossing in the Wadi Khaled region in Syria on Thursday was so intense that stray bullets and rockets landed in Lebanon.
Syrian troops had ambushed the rebels as they tried to flee the besieged area.
Lebanese medical sources said 41 wounded Syrian rebels had crossed a river into Lebanon as they attempted to flee the fighting. Another eight rebels had either been carried in dead or succumbed to their wounds after escaping Syria.
The rebels were driven from al-Hosn in Homs province which the Syrian army surrounded, the medical
sources, who did not wish to be named, said. Syrian state television, meanwhile, reported its army had killed 11 "terrorists" trying to escape al-Hosn.
Earlier this week, Syrian troops seized control of Yabroud, another strategically important Lebanese border town, in the Qalamoun area.
Lebanon's frontier towns, often used by rebels to recuperate, have been increasingly drawn in to the Syrian war, and have recently been bombarded by Syrian helicopters and rockets.
Syrian troops have been on the offensive over the past months in areas close to the border, aiming to cut rebel supply lines across the boundary.