At least 21 civilians, six members of the security forces, and two deserters were killed in violence across Syria on Monday, the Syrian Observatory for Human Rights said.
Near the capital, meanwhile, troops penetrated Rankus, 40 kilometres (25 miles) north of Damascus, after shelling the town which had been encircled for the past six days, the Observatory said.
It said at least 17 civilians were killed in Homs in central Syria.
Security forces stormed the flashpoint city, killing a family of six and a young girl, who was hit by gunfire from a checkpoint in the Karm al-Zeitun district, according to the Britain-based rights group.
Another civilian was killed by gunfire in Karm al-Zeitun, and one in the neighbourhood of Al-Khalidiyeh, also in Homs.
Four civilians were reportedly killed in the Qussur district, while another was hit by machinegun fire in Baba Amro and a man was shot dead by sniper fire in the city's Wadi Iran quarter.
A young man was shot dead in town of Qusseir in the Homs province, the Observatory said.
It claimed that unidentified assailants killed a doctor in Shammas, also in Homs, while the state news agency said Dr Mustapha Safar was shot dead by a "terrorist group."
Separately, rebel soldiers "attacked a minibus carrying six security officers on their way to make arrests in Hirak, killing all of the passengers," said the Observatory, in statements received in Nicosia.
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Government forces responded by deploying two tanks which opened fire and killed three civilians in the southern city of Daraa, it said.
Elsewhere in the province of Daraa, cradle of the 10-month uprising against President Bashar al-Assad's regime, a civilian was killed by indiscriminate gunfire in the town of Saida, the watchdog added.
Near the capital, the Observatory and activists at the scene said deserters pulled out of Rankus as the army moved in. The military assault reportedly claimed the lives of two deserters and left dozens of civilians wounded.
In the eastern suburbs of Irbin and Hammuriyeh, snipers were "shooting at everything that moves," the watchdog said.
Armed clashes also erupted between the army and mutinous soldiers in Hirak, further south in Khirbet Ghazaleh and Saida, as well as in Nassib, a village on the border with Jordan.
Meanwhile, the Syrian state news agency reported a "terrorist group" attacked a gas pipeline in Homs province, near the border with Lebanon.
"An armed terrorist group has targeted a pipeline between Homs and Banias, near the town of Tal Kalakh, in a sabotage operation," SANA reported, without elaborating.
Syrian cities have been subjected to energy shortages for several weeks, which the authorities blame on "armed terrorist groups."
The opposition says the regime carries them out to punish protest hubs.
Since mid-March, Assad's regime has faced an unprecedented protest movement. The United Nations estimated at the start of January that more than 5,400 people had been killed in the ensuing crackdown on dissent.