Ibrahim Abu Laith told Anadolu Agency that Syrian regime and Russian aircraft had bombed several residential areas in Aleppo city.

“Nineteen civilians were killed and 55 others injured, including children and women,” he said.

Abu Laith said that civil defense teams were struggling to extract civilians from under the rubble.

Aleppo has seen an uptick in airstrikes in recent days, coinciding with fierce clashes on the ground between armed opposition groups and regime forces on Aleppo’s outskirts as the latter attempt to tighten their grip on the besieged city.

On Friday, Syrian regime and Russian planes struck opposition-held areas in Aleppo, killing 16 people and injuring 21 others.

UN Emergency Relief Coordinator Stephen O’Brien warned on Thursday that up to 300,000 people are at risk of besiegement in Aleppo.

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

Anadolu Agency