BEIRUT: At least 22 people, including 14 children, were killed in regime air raids on rebel districts of the northern city of Aleppo on Sunday, the Syrian Observatory for Human Rights said.

The Britain-based Observatory also reported that at least 28 people have been killed in Adra, northeast of Damascus, since fighters launched an offensive there.

“An (aerial) attack using explosive-laden barrels over the Sakhur, Ard Al-Hamra and Haydariyeh districts (of eastern Aleppo) killed 22 people, among them 14 children and an 18-year-old boy,” said the Britain-based Observatory.

The Aleppo Media Center (AMC), an activist network on the ground, reported several helicopter attacks on rebel-held areas of the city.

Once Syria’s commercial capital, Aleppo has suffered massive destruction since a rebel offensive in July last year.

The city is now divided into pro- and anti-regime areas, and according to the AMC, the regime uses its air force near daily to target rebel districts.

The helicopters, said the group, dropped explosive-laden barrels on several neighborhoods, causing widespread destruction.

Also in Aleppo, the Syrian Red Crescent on Saturday delivered food and medicine to the central prison, which has been under rebel siege for eight months.

The volunteers escorted out 15 prisoners, said the Observatory, adding that "another 341 detainees are waiting to be released."

President Bashar Assad's regime earlier this week announced an amnesty for scores of detainees at the jail "because of the poor health and humanitarian conditions," according to the Observatory.

Meanwhile, northeast of Damascus, at least 28 civilian members of minority religious communities have been confirmed dead in Adra since Wednesday, when Islamist rebels launched an offensive aimed at capturing the key entrance into the capital.

"The number of civilian fatalities has risen to 28," said the Observatory, which relies on a broad network of doctors, activists and lawyers across Syria for its reports.

The army has vowed to "crush" rebels in the industrial town, which has seen fierce fighting for five days.

More than 126,000 people have been killed in Syria since March 2011, and millions more have fled their homes.