Syrian warplanes bombed rebel areas near Damascus as President Bashar Assad's troops battled opposition fighters for control of the road linking the capital to the country's largest airport.
Mr Assad's forces are trying drive out rebels who have established enclaves in the suburbs. While the government has lost control of large swathes of territory in the country's north and east, including parts of the northern city of Aleppo, the capital remains tightly secured.
Conditions in the city have worsened however, with prices for basic goods rising and fuel in short supply. US officials said today that they believe Mr Assad's sister and mother have left the country, suggesting that hardship has reached even the leadership's families.
The Britain-based Syrian Observatory for Human Rights reported bomb attacks and clashes in a number of Damascus suburbs, saying at least 13 people were killed. The group, which relies on a network of contacts inside Syria, said fighter jets bombed the south-western suburbs of Daraya and Moadamiyeh, where rebels have been fighting regime forces for weeks.
Because of its strategic location near a military airport, Syrian troops have been pounding rebel positions in Daraya for weeks. Earlier this month, the government claimed its troops had regained control of much of the district.
Activists posted a video of the Daraya fighting online which showed artillery shells slamming into concrete buildings, sending plumes of thick, grey smoke into the sky.
Daraya is flanked by the districts of Mazzeh, home to the military air base, and Kfar Sousseh, where the government headquarters, the General Security intelligence agency's head office and the Interior Ministry are located.
The Observatory also reported heavy fighting near Damascus International Airport and said the regime was shelling the town of Aqraba along the airport road.
State-run news agency Sana said troops have been battling rebels in the oil-rich province of al-Hasaka in the country's north-east, killing and wounding several "terrorists" - the term the government and state media use to refer to rebels.
Also in the north, Sana said terrorists shot and killed a maths teacher, Nabih Jamil al-Saad, near his home in the town of Hmaida in Raqqa province yesterday. A day earlier, rebels killed Mamdouh Abudllah Bin Abd Dibeh, a cardiologist, in front of his clinic in Sheik Mheddin area of Damascus, Sana said.