“Warplanes carried out two consecutive raids against areas under siege in Homs city, as well as carrying out heavy shelling against the same districts,” the Syrian Observatory for Human Rights said.
“The shelling is focused on the neighbourhoods of Khaldiyeh, Bab Hud, Hamidiyeh and Bustan al-Diwan in an unprecedented manner.”
The Britain-based group said regime forces were using mortar shells, rockets, tank shells and heavy artillery in the assault.
Observatory director Rami Abdel Rahman said troops were trying to storm Khaldiyeh and that fighting was underway around the Old City.
Khaldiyeh and the Old City have been under siege by the army for around a year. Homs, the third largest-city in the country, was one of the first to join the revolt against President Bashar al-Assad’s regime more than two years ago.
A security source in Damascus confirmed fierce fighting was underway in Homs. “Military operations never stopped in Homs, but their pace increases according to priorities,” he told AFP.
“What’s important is to cleanse those neighbourhoods of Homs that are in the hands of armed terrorists, particularly Khaldiyeh, Hamidiyeh and the Old City,” he added.
“The army is advancing on all fronts but at varying speeds,” he said, insisting: “Advances may be slow but they are real.”
Syrian state television said government troops were making “great progress” in Khaldiyeh where they “eliminated large numbers of members of armed terrorist groups” — the term used by the government to describe the rebels.
An activist in Khaldiyeh told AFP on Saturday afternoon that the fighting had subsided somewhat since the morning.
“Today was the beginning of a new offensive,” he confirmed, describing air raids and shelling on the town.
“The situation is even worse than before, we’re suffering shortages of basic materials such as rice and sugar,” he told AFP over the Internet.
On Thursday, Syrian regime troops took the town of Al-Qariatayn, in Homs province as part of a wider campaign to gain ground in the central region.
The Observatory chief said the army appeared to be trying to “isolate the south of (central) Hama province and the north of Homs province to cut the supply lines between the two provinces.”