Fierce clashes between troops and rebels erupted on Thursday for the first time in a Sunni Muslim village in the Alawite-majority coastal region of Banias in northwest Syria, a watchdog said.
"Since this morning, the army and pro-regime forces have been besieging the village of Bayda at the southern entrance to the town of Banias," the Britain-based Syrian Observatory for Human Rights said.
"The village is the scene of fierce fighting between the army and rebel battalions -- the first of its kind in the Banias area," added the watchdog which relies on activists and medics on the ground for its information.
The Banias region is predominantly Alawite, an offshoot of Shiite Islam and the sect of President Bashar al-Assad, but has several Sunni villages to the south.
In the south of the port city, where there is also a large Sunni population, "sustained gunfire coming from the army was heard, and the security services are out in the streets to terrify residents," the watchdog said.
Witnesses have seen "ambulances taking soldiers wounded in the fighting to Bayda," it added.
The Observatory said most young Sunnis left the Banias area after an army offensive in May 2011, two months after the start of the uprising against the Assad regime.
"They left because they were afraid of being arrested or forced to join the army," Observatory director Rami Abdel Rahman said.
Banias, along with Daraa in the south, the cradle of the uprising, saw some of the first demonstrations against the regime in March 2011.
The region's three main coastal cities of Banias, Latakia and Tartus and their surrounding areas form the "Alawite heartland" where analysts say Assad could seek refuge if his regime falls.