Syrian opposition fighters have re-entered the historic Christian town of Maalula north of Damascus, as they battle regime troops in the surrounding Qalamoun region, a monitoring group said on Saturday.
"Fierce clashes are under way between rebel fighters, including the Al-Nusra Front, and regime troops in Maalula, which the rebels have entered and are trying to gain control of," said Rami Abdel Rahman, director of the Syrian Observatory for Human Rights.
Government forces repelled a rebel advance into Maalula in September, after heavy fighting that prompted most of the town's residents to leave.
The picturesque town is considered a symbol of the ancient Christian presence in Syria, and its 5,000 residents are among the few in the world who speak Aramaic, the language of Jesus Christ.
The renewed clashes in the town come as the regime battles to gain control of a string of strategic towns and villages along the Damascus-Homs highway, north of the capital.
It has recaptured the town of Qara and Deir Attiyeh, and government troops are now battling rebels for control of Nabak.
On Saturday, the Observatory said fighting was continuing in Nabak, and that regime forces had launched several air strikes on the town, as well as on nearby Yabroud and its environs.
A Syrian security source told AFP this week that government forces plan to secure Nabak and then move farther south to Yabroud.
They are seeking to encircle the rebels in the Qalamoun region north of Damascus and sever opposition supply lines across the nearby border with Lebanon.