Heavy Airstrikes Resume over Syrian City of Aleppo

The Syrian city of Aleppo awoke Thursday morning to bury their dead after renewed overnight shelling left at least 45 people dead. The airstrikes, apparently targeting rebel militias, were the heaviest in months and represent the resumption of hostilities following a détente negotiated last week by Russia and the U.S.

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No one has yet claimed responsibility for the strikes but U.S. Secretary of State John Kerry blames the Russian and Syrian governments for the attacks targeting Syrian rebels. While speaking at the U.N. Security Council Wednesday, Kerry pleaded with Russia and Syria to halt further bombing missions over Syria and said the cease-fire, which took effect Sept. 12, was now “hanging by a thread.”

"It's as if the planes are trying to compensate for all the days they didn't drop bombs … It was like there was coordination between the planes and the artillery shelling, because the shells were hitting the same locations that the planes hit," said Ammar al-Selmo, head of the civil defense rescue service in opposition-held eastern Aleppo to Reuters.

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The British-based monitoring group, Syrian Observatory for Human Rights, said that the strike was the heaviest airstrike in months.

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The United Nations earlier said on Thursday that it was resuming aid convoys to the city, after an airstrike on a Syrian Red Crescent convoy killed at least 20 people.

The U.S. blamed Russia for the attack on the convoy, but Russia said the U.S. “has no facts” to back up their claims and called for a "thorough and impartial investigation" into the convoy attack.

Russia claims that a U.S. Predator drone was reported in the area where the convoy was destroyed.

The cease-fire was already unstable on Saturday after U.S. aircraft bombed Syrian Arab Army positions, killing at least 62 soldiers.