At least 44 people were killed in and near the Syrian capital Sunday in regime air strikes and rebel mortar fire, reports from a monitoring group and state media said.

The Syrian Observatory for Human Rights said at least 32 people were killed in air raids on two rebel-held towns near Damascus.

Seventeen were killed in Douma, northeast of the capital, and 15 in Kfar Batna, to the east, said Observatory head Rami Abdel Rahman. A woman and child were killed in each of the towns.

State news agency SANA, meanwhile, said 12 people were killed in rebel mortar fire on southern districts of Damascus.

"Twelve people including a girl were martyred and 23 others wounded in terrorist attacks with mortars on the Shaghur, Bostan al-Dur and Dauilaa districts," it said.

With the more than three-year-old conflict raging across Syria, the rebel bastion of Douma has been besieged by regime forces for more than a year, and it has been the target of regular bombardment.

Activists on the ground confirmed Sunday's air raids, saying that markets had been the targets.

Both towns are in the Eastern Ghouta region in the east of Damascus province.

Syria's conflict is estimated to have killed more than 170,000 people and displaced around half of the population since it broke out in March 2011.