DAMASCUS, Dec. 11 -- Radical fighters from the al- Qaida-linked Nusra Front stormed a suburb of the Syrian capital of Damascus on Wednesday, killing tens of civilians, some of whom are state servants, the pro-government Sham FM radio reported.

Following their defeat in three major towns in the rugged al- Qalamoun region north of Damascus, the rebels stormed Wednesday the Adra al-Umalieh suburb, a couple of days after the army dislodged them from the town of al-Nabek.

The Sham FM radio said the bodies of tens of civilians were still scattered on streets in Adra and more than eight civilians were slaughtered over sectarian affiliations.

"The Nusra militiamen are fanned out on the town's streets," the report said, adding that thousands of Adra's residents have fled to the nearby Hafir al-Tahta and al-Qutaifa areas, while thousands of others have cowered in their homes fearing "to be slaughtered" by the Nusra fighters.

While saying that the radical fighters were burning the homes of the state servants in the town, the radio said the army unites are now besieging the town in a bid to storm it to rid its residents of the hard-liners.

Al-Qaida-linked groups such as the Nusra Front and the Islamic State of the Iraq and the Levant have taken advantage of the anti- government movement in Syria, emerging as a serious force among the rebel groups.