The Syrian army launched a new assault on Monday in the restive northern province of Idlib and the city itself, where residents are suffering "indescribable" humanitarian conditions, activists said.
"The army bombarded the Dbeit district in Idlib city and pounded the Ath-Thawra neighbourhood, where several buildings collapsed," an anti-regime activist in the city told AFP via Skype, giving his name only as Yasser.
He reported tanks and armoured cars driving around inside the city.
"The humanitarian situation is indescribable, the residents are totally without water and electricity, and communications have been cut off," he added.
While the army controls some parts of the city that were wrested from the rebels in an assault on Saturday, others remain in the hands of the insurgents.
Signup to our newsletter and follow us on Facebook and Twitter!
In Dbeit, 20 bodies were discovered on Sunday night, according to Rami Abdel Rahman, head of the Syrian Observatory for Human Rights.
On Monday, security force gunfire killed at least two people in the Idlib town of Maaret al-Numan and in the Hazzan area, the Britain-based Observatory said.
"The government forces have also bombarded the Maaret Masrin area, near Idlib city," Abdel Rahman added.
Scores of people were killed in a ferocious weekend assault by regime forces against rebel bastions in Idlib province, with troops pouring into the city on Saturday.
The assault came 10 days after the Homs neighbourhood of Baba Amr was stormed, capping a month-long blitz in which hundreds died.