Heavy fighting is continuing around the Syrian capital, as government forces try to halt a rebel advance.

Activists said clashes continued in Jobar district in Damascus on Friday amid rocket shelling by government forces on the eastern district and nearby neighbourhoods.

While opposition fighters have seen gains across parts of the country, they have so far been kept away from the centre of Damascus.

But in the past three days, rebels have overrun army positions encircling the heart of the city.

Early on Friday, a rocket fired by government forces hit the Damascus suburb of Moadamiyah, killing six rebel fighters and injuring 12 other people, opposition activists said.

More people have been injured in overnight bombardment in the Damascus neighbourhoods of al-Hajar al-Aswad, al-Qadam, al-Assali and Barzeh, according to activists.

Syrian state media, meanwhile, reported that six people, including three children, had been killed on Wednesday when "terrorists" fired two mortar shells on a bus station in al-Qaboun district in Damascus.

'Pursuing terrorists'

SANA state agency also reported that government forces continued to pursue "armed terrorist groups" in the Damascus suburbs of Arbeen, Zamalka and Adra al-Balad, Tal Kurdi, Douma Farms and Harasta, "inflicting heavy losses upon their members".

State media regularly refers to armed rebels fighting President Bashar al-Assad forces as "terrorists".

Regime forces are battling to retake control of an 8km belt around the heavily guarded capital.

In the central city of Homs, heavy bombardment was reported in the Old Homs district in the centre of the city. The rebel-held area has been under tight siege by government forces for the past nine months.

In rebel-held Kafaraya on the outskirts of Homs, activists posted a video showing several rockets falling at once on Friday morning.

SANA said that "a number of terrorists were killed in a series of operations" in the area.

Violence in the country shows no sign of abating since the uprising against Assad began in March 2011. The UN estimates that more than 60,000 people have killed over the past two years.