Amman: Syrian troops backed by tanks and artillery moved into a rebel-held district of Damascus on Monday, stepping up efforts to drive opposition fighters from the capital and build on battlefield gains elsewhere in the country, a rebel commander said.

Opposition sources said troops loyal to President Bashar Al Assad advanced into the neighbourhood of Qaboun after subjecting the district to heavy shelling. Two adjacent rebel-held neighbourhoods have been under sustained fire in recent weeks to cut off the movement of rebel fighters.

Diplomats and security sources said Al Assad appeared intent on securing the capital from rebels that pose a threat to his troops, who are dug into positions in the centre of the city.

Backed by fighters from the Hezbollah, Al Assad has recaptured important regions in central Syria in the past two months, linking Damascus to his Alawite heartland on the coast. His troops now appear focused on eliminating the rebel threat to the capital.

In Qaboun, Republican Guards troops detained hundreds of people in public places to prevent rebel fighters from hitting government troops as they breached rebel defences and entered the district, activists said.

There was no immediate comment on the fighting from the Syrian government and Reuters was not able to verify opposition accounts.

Qaboun contains an industrial area through which rebels had been linking up with opposition units in the north-eastern suburb of Harasta.

Republican Guards units overran the industrial area and besieged Qaboun with T-72 tanks while units on high ground in the centre of the capital hit Qaboun with rockets and artillery, according to a rebel commander there.

“They made inroads into Qaboun. We are still on the high buildings but they took lots of civilians to prevent us from hitting them,” said Mohammad Abu Al Hoda of the Free Syrian Army.

He said the hostages were being held in a mosque and two schools.

The Qaboun Coordination Committee, an activist group, said at least 60 people had been killed in Qaboun over the last few days by the shelling and subsequent clashes.

A working class district, Qaboun was one of the first areas of Damascus to demonstrate against four decades of rule by Al Assad and his late father before becoming a centre of armed resistance after security forces killed dozens of protesters.

The conflict has taken on a sectarian dimension seen elsewhere in Syria, with Qaboun pitted against an adjacent neighbourhood inhabited by members Al Assad’s Alawites.

The opposition Syrian National Coalition said in a statement that 200 people were trapped in a mosque in Qaboun and 40,000 civilians in Qaboun and nearby Barzeh have been under siege for the last seven months and face the threat of being wiped out by indiscriminate shelling.

The Syrian Observatory for Human Rights, a pro-opposition monitoring group, said that the detained residents were able to flee the mosque on Saturday. But it said locals were struggling to cope with shortages of food and medicine and the presence of snipers.