BEIRUT: At least 36 people, including 15 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.
They were killed when regime forces unleashed an aerial attack using explosive-laden barrels over six districts in eastern Aleppo, including Sakhur, Ard al-Hamra and Haydariyeh, said Observatory director Rami Abdel Rahman.
Fifteen children, an 18-year-old boy and a woman were among 36 people killed, he said, updating an earlier toll and warning the number could rise because many people were wounded, some in critical condition.
The Aleppo Media Centre (AMC), an activists network on the ground, reported several air 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.
An AMC activist in the city, Mohammed al-Khatieb, said in a message posted on Facebook that the raids were "unprecedented."
"Everyone is looking up at the skies and watching the planes. But there's nothing to be done," he said.
Barrel bombs were dropped on some 10 neighbourhoods of the city, Khatieb later told AFP, adding: "Many people have been killed."
The bombings came a day after the Syrian Red Crescent delivered food and medicine to Aleppo central prison, which has been under rebel siege for eight months.
Earlier this week, the government announced an amnesty on humanitarian grounds for scores of prisoners held on criminal charges.
Fifteen prisoners have already been freed, escorted out of jail by volunteers, according to the Observatory, while 341 others are waiting to be released.
In Adra, northeast of Damascus, at least 32 civilians have been confirmed dead since Wednesday when Islamist rebels launched an offensive aimed at capturing the key entrance into the capital, said the Observatory.
The group, which had earlier reported a toll of 28, added that at least four of the dead were women, and that most of the fatalities belonged to President Bashar al-Assad's Alawite sect.
"Reports have also surfaced of dozens of people missing from Adra," said the Observatory, which relies on a network of doctors, activists and lawyers on the ground for its reports.
The army has vowed to "crush" Islamist rebels in the industrial town, which has seen fierce fighting for five days.
Most of the country's Alawites -- whose religion is an offshoot of Shiite Islam -- support Assad, and many members of other minority groups fear a Sunni Islamist victory in the Syrian conflict.
More than 126,000 people have been killed in Syria since March 2011, and millions more have fled their homes.