Speaking to Anadolu Agency, Ibrahim Abu Laith said most fatalities in the shelling in the opposition-held Jib Al-Quebeh neighborhood in eastern Aleppo were women and children, who had fled their homes due to regime attacks.

He expected the death toll from the shelling to rise.

On Tuesday, at least 51 civilians were killed and scores injured in regime airstrikes on eastern Aleppo.

Since mid-November, more than 739 civilians have been killed -- and hundreds more injured -- in regime attacks on eastern Aleppo, according to figures released by local civil defense officials.

Syrian regime forces have recently stepped up attacks on opposition-held parts of eastern Aleppo in an effort to retake the city and advance on Idlib, one of the Syrian opposition’s last strongholds.

The fierce bombardments have forced hospitals and other medical facilities in the war-battered city to cease operations while most academic activities have been completely halted.

Syria has been locked in a devastating civil war since early 2011, when the Bashar al-Assad regime cracked down on pro-democracy protests -- which erupted as part of the "Arab Spring" uprisings -- with unexpected ferocity.

Since then, hundreds of thousands of people are believed to have been killed and millions more displaced by the conflict.