The Syrian air force Sunday attacked Lebanon's border town of Arsal, reported Xinhua.
The raid targeted the crossings and mountainous road linking Arsal to the Syrian town of Flita, Xinhua quoted a source as saying, adding that the results of the raid were unclear.
The source, however, denied rumours suggesting hundreds of gunmen who fled the Syrian town of Yabroud have entered Arsal after the Syrian army seized control Sunday.
The Lebanese army deployed in the area fortified its positions and took special measures to counter the possibility of the gunmen entering Arsal, the source added.
Arsal lies on the eastern borders of Lebanon, adjacent to war-torn Syria. It has been a main smuggling crossing point for gunmen and ammunition to the rebels fighting against the government of Syrian President Bashar Assad.
Arsal also hosts around 50,000 Syrian refugees, which is approximately the same number of its residents.