Fifty-six people were killed and 220 injured Saturday by Assad regime and Russian airstrikes on residential areas in opposition-held parts of Syria's northwestern city of Aleppo, Najib Ansari, a civil defense official said.
Ansari noted that the warplanes targeted the districts of Bustan al-Qasr, Mashhad, al-Kallasa, Salihiya, and al-Fardos, all currently under siege by the Bashar al-Assad regime.
Earlier, the Syrian Observatory for Human Rights (SOHR), a UK-based monitoring group, said the attack targeted civilians in the area controlled by the opposition group.
Local sources said Russian jets conducted intense airstrikes on the besieged area in the earlier hour of the day, while Assad's forces started attacks in Handarat Camp in the north and Sheikh Said areas south of the city.
The casualties include women and children.
The death toll is expected to rise due to limited capacity to rescue victims trapped under collapsed buildings.
Medical facilities in the area were also destroyed by regime and Russian warplanes on Friday killing 86 people.
Aleppo has been recently suffered from intense attacks by regime and Russian forces.
The Syrian government and its closest ally Russia, intensified its airstrikes after a Russia-U.S. backed week-long ceasefire earlier this month.
Since Sept. 19, at least 323 civilians have been killed and 1,334 injured by Assad regime and Russian airstrikes on Aleppo, according to civil defense officials and medical sources in the city.
The attacks have targeted districts in the eastern part of Aleppo besieged by regime forces.
Both cluster and chemical bombs were reportedly used during attacks on civilians and medical workers in Aleppo.
The Russia-Assad forces are also accused of bombing the UN aid convoy during the ceasefire that killed dozens of aid workers.
Around 500,000 people, mostly civilians, have been killed in Syria since the devastating civil war began in 2011.
More than 11 million people, almost half the country's population, were displaced and forced to live a refugee life in neighboring countries as well as inside Syria.
Turkey repeatedly insisted on a no-fly-zone in northern Syria in order to shelter the displaced people and provide them a safe place inside their own country.
