Syrian warplanes launched air raids in Damascus province on Friday after overnight bombardments and clashes across the country, the Syrian Observatory for Human Rights watchdog said.

"The air force for the first time attacked the Assal al-Ward area in the Kalamun region, killing one civilian, wounding dozens and destroying several homes," the Britain-based group said in a statement.

It said the military on Thursday withdrew from several areas in the province but that further air raids were expected as regime forces sought to take back areas they had lost after rebel attacks on military checkpoints.

The Observatory, which relies on a countrywide network of activists and medics in compiling its information and tolls, also reported fighting and bombardment in several districts of the capital itself overnight.

It said several rockets hit the Qaboon district in the northeast of the city and that clashes between rebels and the army erupted in the southern neighbourhood of Qadam, which was also bombarded.

Fighting also took place in southern Damascus in Daraya, which President Bashar al-Assad's forces have been trying to retake for weeks, the watchdog said.

There were also clashes in Yalda in the south and Douma in the northeast, as well as an attack on a military position northeast of Damascus between the provincial town of Irbin and the suburb of Harasta.

Elsewhere, a sniper shot dead a man in a Palestinian refugee camp in Daraa in the south, and fighting was also reported in areas near the border with Jordan, the watchdog said.

In the north, clashes took place in several neighbourhoods of the country's second city Aleppo, including around a military compound besieged by rebels, and several districts of Deir Ezzor city in the east were bombarded.

Overnight shelling was also reported in the central provinces of Hama and Homs.

On Thursday at least 142 people were killed in violence across Syria, said the Observatory which has reported a death toll of more than 45,000 since protests against Assad that erupted in mid-March 2011 became an armed rebellion.