Two Damascus suburbs came under heavy tank bombardment on Wednesday following renewed rebel attacks on forces loyal to Syrian president Bashar al-Assad.
Artillery and anti-aircraft gun barrages hit the suburbs of Harasta and Irbin, retaken by Assad's forces from rebels two months ago, as army helicopters reportedly flew overhead.
The Free Syrian Army mounted a series of operations after nightfall and the army is retaliating strongly," Raed, one of the activists, told Gulf News from just outside the capital.
Raed said rebels armed with small arms and rifle propelled grenades had attacked a large compound belonging to Airforce Intelligence, which has been at at the forefront Assad's bloody crackdown.
The Syria Free Army also reportedly attacked army roadblocks in the suburbs.
Other activists reported tank shelling near the Damascus-Aleppo highway, which runs along the two suburbs, and north of the Damascus neighborhood of Barzeh.
Assad's forces reasserted control of Damascus suburbs at the end of January, after several days of tank and artillery shelling. However, analysts say Assad's inability to maintain security control in his capital is a sign of his regime's growing weakness.
Shelling densley populated civilian areas has become a standard tactic for Assad's forces, who have also shelled Deraa, Homs, Idlib, and Rastan.
At least 700 were killed in 26-days of straight shelling in Homs in February, after which Assad's forces reportedly conducted mop-up operations that included the systemic rape, torture, and mass executions.
Reports of war crimes have become increasingly common as Assad ramps up his bloody crackdown on the year-long popular uprising against his rule.
UN Human Rights officials say at least 8,000 civilians have been killed by Assad's forces.
Wednesday's shelling came even as the UN Security Council issued a presidential statement calling on Assad to immediately order a ceasefire.