At least eight civilians were killed Thursday in ongoing military operations in Syria's troubled provinces of Hama and Homs, a rights group said.

"Six civilians were killed and nine others were wounded, five of them critically, in operations by Syrian forces in the town of al-Tremeesa," the Syrian Observatory for Human Rights said in a statement received in Nicosia.

Further south in the flashpoint province of Homs, two civilians were killed by security forces, one of them allegedly by sniper fire, the Britain-based Observatory said, adding that a third man died of gunshot wounds sustained a day earlier.

The Observatory said residents in the Homs town of Tal Kalakh reported the presence of militias loyal to President Bashar al-Assad patrolling the area and said "heavy and light machine gunfire" was heard.

Tal Kalakh residents feared that government troops were preparing to raid the town, the statement added.

In the country's southern Deraa province, the Observatory said Syrian forces withdrew from the town of Dael, a day after seven members of Assad's security forces were killed there in clashes with army deserters now fighting to overthrow the embattled regime.

On Wednesday, 14 civilians, including a woman and a 12-year-old boy, were killed by security forces in several Syrian provinces as the eight-month government crackdown on protesters demanding Assad's ouster continued unabated.

According to an early November UN estimate, more than 3,500 people were killed in the Syrian government crackdown on dissent since mid-March.