Damascus,in a tragic incident, at least seven people were killed and 20 others suffered suffocation and breathing difficulties from chemical gas attack in Aleppo.

The Nour Addien al-Zinki rebel group on Monday fired rockets filled with poisonous gas on the government-controlled Salahuddien district in Aleppo.

On Tuesday, meanwhile, the rebels also accused the government of dropping barrel bombs stuffed with chlorine gas on the rebel-held town of Saraqeb.

Russia had informed the US about the rebel use of poisonous materials in Aleppo.

According to sources,“seven people were killed and 41 others were injured on Wednesday by fresh rebel shelling on the government-controlled parts of Aleppo”.