By Khalid Suleiman

ALEPPO, Syria

At least 46 civilians were killed and hundreds injured in airstrikes carried out by regime forces and Russian warplanes in Syria’s northern city of Aleppo on Saturday.

Local civil defense official Ibrahim Abu Laith said the raids targeted opposition-held neighborhoods in eastern Aleppo. 

“Forty-six people were killed and 325 others injured in the bombardment,” he told Anadolu Agency. 

Regime forces have tightened up its siege and attacks on opposition-held areas in eastern Aleppo in an effort to retake Aleppo and advance to Idlib, the opposition’s last stronghold. 

More than 508 civilians have been killed and 1,871 others injured in regime attacks on eastern Aleppo since mid-November. 

In the last 10 days, all hospitals and medical facilities stopped operating because of the attacks while schools were disrupted. 

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.