TEHRAN (Press Shia) – Dozens of Syrians lost their lives after Takfiri terrorists fired mortars containing chemical agents against civilian areas in eastern Aleppo as Syrian troops continue to make gains on the ground in the embattled northwestern city.

On Sunday night, the Takfiri militants fired several mortar shells, some of which filled with chlorine gas, at Karam al-Tarrab neighborhood, west of al-Nayrab airport in eastern Aleppo, killing nearly 30 civilians and army troops.

The attack came after the Syrian army gave an ultimatum on Sunday to the terrorists to leave eastern neighborhoods of Aleppo in 24 hours or face a full-scale operation by the army.

Aleppo has been divided over the past four years between Syrian forces in the west and terrorists in the east, making it a frontline battleground.

Backed by Russian air cover, the Syrian army launched operations to reunite the divided northwestern city in September.

Since March 2011, Syria has been hit by militancy and terrorism backed by Western states and their regional allies.

According to a report by the Syrian Center for Policy Research, the conflict has claimed the lives of over 470,000 people, injured 1.9 million others, and displaced nearly half of the country’s pre-war population of about 23 million within or beyond its borders.