At least 15 people were killed by troops across Syria on Saturday, as the army cracked down on rebel strongholds, the Syrian Observatory for Human Rights said.
In the central province of Homs, five civilians were killed by gunfire and shelling by regime troops, including two in the rebel stronghold of Qusayr and a third elsewhere in the province.
The others were killed in the Khaldiyeh and Baba Amr districts of Homs city, where the Britain-based watchdog troops have bombarded several neighbourhoods in an attempt to regain control.
Also in central Syria, two civilians were killed in the city of Hama in a dawn ambush by regime forces, and a third was killed when clashes broke out between troops and rebels elsewhere in Hama province.
In the town of Mahaja in the southern province of Daraa, the cradle of the revolt against the regime of President Bashar al-Assad, shooting broke out as troops used tanks to storm the area.
Elsewhere in Daraa, one civilian was killed in gunfire in a raid by regime troops, while in northern Aleppo province, two people, including a rebel fighter, were killed.
Three civilians, including a child, were killed by sniper fire in the eastern city of Deir Ezzor, the Observatory said, adding that fierce clashes broke out between troops and rebels in the city.
A man was also shot dead by sniper fire in the Damascus suburb of Douma, labeled a "disaster area" by local activists, who posted videos showing deserted streets littered with debris from shelled buildings.
"Residents evacuated their homes due to the heavy shelling on peaceful residences," the narrator said, in a video posted to YouTube.
On Friday, tens of thousands of people demonstrated against the regime and called fellow citizens to action under the slogan: "If the government are traitors, where are the people?"
"Bashar, hey you! We don't want you!" chanted demonstrators in Bukamal, in the eastern province of Deir Ezzor, pounded on the same day by the army.
Activists saluted the Syrian pilot who defected on Thursday with a sign reading: "The Syrian people salute air force Colonel Hassan al-Hamade for his defection and his refusal to fire on his own people."
Protests were also held several neighbourhoods of Deir Ezzor city, despite shelling and clashes between troops and rebels, which left 34 people killed.
And in the town of Al-Quria, protests broke out following the withdrawal of regime forces from military checkpoints, local activists said.
In a video posted to the Internet by activists, at least 100 people could be seen chanting: "Get out shabiha," referring to pro-regime gunmen.
Meanwhile, state news agency SANA reported that a Syrian-Arab Red Crescent (SARC) volunteer was killed in Deir Ezzor province on Friday morning.
The volunteer paramedic was killed by an "armed terrorist group in the area of al-Rashdiyeh in Deir Ezzor," SANA said, adding that he was wearing his Red Crescent uniform at the time.
SARC "denounced the attacks against its members," SANA said, and reiterated its demands that "all sides provide safe access for its volunteers so that they can provide aid to those who need it".
At least 116 people, including 69 civilians, 31 members of pro-regime forces, and six rebels, died across Syria on Friday.