More than 30 people have been killed in the most lethal rebel bombardment of the city of Aleppo since Syria's conflict started four years ago, a group monitoring the war said on Tuesday, an attack condemned by a U.N. envoy visiting Damascus. Staffan de Mistura called the shelling an indiscriminate attack on civilians but said the government should not retaliate by dropping barrel bombs on populated areas in the divided city. Syrian President Bashar al-Assad told De Mistura the world needed to recognize the threat of terrorism and prevent foreign states from arming insurgents, state media reported following their meeting on Tuesday. While large civilian death tolls are frequently reported as a result of Syrian army aerial bombardment of rebel-held parts of the northwestern city, lethal shelling of government-controlled areas is more unusual. Diplomats and analysts tracking developments in Syria expect intensified battles for Aleppo and other parts of western Syria in the coming weeks after insurgent advances in the northwest, central Syria and the south. The British-based Syrian Observatory for Human Rights said 34 people were killed, including 12 children, and about 190 were wounded in the bombardment by rebels who are seeking control of the city. State media had said on Monday that at least 23 people were killed. The attack targeted a mosque where children were taking religious lessons as well as other neighborhoods, it said. State news agency SANA published a picture of a limp, blood-soaked child in the arms of a man and another of an older woman in clothes stained with blood and being attended to by medics. The Observatory, which tracks the conflict using sources on the ground, said the insurgents fired more than 300 shells on government-held neighborhoods in Aleppo. The army and rebels have been in a long battle for Aleppo, which was Syria's economic and industrial hub before rebels took over parts it in July 2012. De Mistura has previously tried to broker a ceasefire in Aleppo.
