Security forces were also sending reinforcements to the northern province of Aleppo, where some swathes of territory have been in militant groups’ hands for months.
According to reports, clashes broke out at dawn between the army and militant groups on the outskirts of Dabaa village" north of Qusayr near the border with Lebanon.
Official Syrian media had reported that Dabaa fell on Thursday.
Lebanese channel of Al-Manar also quoted a general as saying his troops had launched a surprise attack. This was aimed at the liberation of Dabaa outskirts from terrorist groups, he said.
A second militant bastion north of Qusayr, Eastern Bweida was also totally cleared in the latest operation of army late on Thursday.
Dozens of militants were killed in the latest round of clashes in Dabaa and Eastern Bweida, the local media said.
Analysts say Syrian army troops will now turn their attention on the central city of Homs, where some areas are still in rebel hands.
Army forces were also massing "in their thousands" in Aleppo province in the north, aiming primarily to take full control of areas along the border with Turkey.