Fierce clashes raged Friday between Syrian troops and rebels in northeastern Damascus as government warplanes raided insurgent strongholds, a monitoring group said.

The Britain-based Syrian Observatory for Human Rights said at least seven rebels were killed in regime shelling and air raids in the district of Jobar.

Violence has escalated in Jobar since February 9 when a Jordanian suicide bomber from the jihadist Islamic State of Iraq and the Levant killed 32 government forces.

Since then clashes have intensified between the rebels and forces loyal to President Bashar al-Assad, said the Observatory which relies on a network of activists and medics on the ground for its reports.

Friday's shelling also spilled into the district of Qabun further north of Jobar, the Observatory said.

In other violence, regime forces stormed the village of Khirbet al-Naqus in the central province of Hama on Friday and reportedly killed nine men, said the monitoring group.

It quoted activists as saying the men were "summarily executed" in the village square.

Five children were killed, meanwhile, in regime air raids in the northern province of Idlib.

More than 140,000 people have been killed in Syria's conflict since March 2011, and millions more have fled their homes.