Syrian jets Monday bombed Baba Amr in a bid to repulse a rebel attack on the strategic neighbourhood of Homs city, a watchdog said, adding that street battles erupted intermittently during the night.
Rebels launched their assault on Baba Amr at dawn on Sunday, hoping to take back the neighbourhood which they lost to President Bashar al-Assad's forces a year ago.
The attack sparked fierce fighting on the ground and shelling and air strikes by regime warplanes.
"The army will at all costs hunt down the rebels even if it destroys the neighbourhood," said Rami Abdel Rahman, head of the Britain-based Syrian Observatory for Human Rights.
"The regime cannot allow them to stay ... because the neighbourhood of Baba Amr is known as an (anti-regime) symbol in the international media."
Abdel Rahman said residents of the neighbourhood had fled to other districts of the central Syria city.
The pro-regime Al-Watan newspaper reported that a unit of the regime army clashed with gunmen and "terrorists from the Al-Nusra Front (jihadist group) who tried to infiltrate Baba Amr."
"A number of armed men were killed and wounded," it said.
The Observatory said at least 175 people were killed across Syria on Sunday -- 79 regime soldiers, 50 rebels and 46 civilians. The soldiers were killed in fighting and executions, the watchdog added.
Rebels said their assault on Baba Amr was a bid to take pressure off other rebel-held areas following the launch last week of a widescale army offensive in Homs, which has been dubbed 'capital of the revolution' against President Bashar al-Assad's forces.
Regime troops seized Baba Amr from rebels just over a year ago after a bloody month-long siege that left the district in ruins and claimed hundreds of lives, including those of two foreign journalists.
On Sunday, Abdel Rahman said the surprise dawn assault by rebels came after troops had reduced their presence in Baba Amr to target other rebel-held districts.