Opposition sources say 20 people have been killed after the Syrian Army shelled rebel positions inside a Palestinian refugee camp on the outskirts of Damascus.
Meanwhile, activists say Syrian rebels have captured a key oilfield in the province of Deir Ezzor after a siege lasting several days.
If the reports are independently confirmed, it will be the first time opposition forces have taken control of an oilfield.
A car bomb has also exploded in the centre of Damascus, close to a government military complex.
Seven people were injured, one of them critically. A nearby hotel was also caught in the blast.