Bombing campaign in Syria kills dozens, destroys buildings

of their districts and shelled government neighborhoods, wounding several people, according to state media.

Diplomatic efforts in New York have failed to salvage a Syria ceasefire that lasted nearly a week, before giving way to what residents and activists say is a new level of violence. The bombing, which began in earnest late Wednesday, has been unprecedented, targeting residential areas, infrastructure and civil defense centers.

Aleppo, Syria’s largest city and one-time commercial center, has been contested since July 2012, but in recent weeks its eastern rebel-held neighborhoods have been under siege by government forces and their allies. During the cease-fire, aid convoys remained stuck on the Turkish border unable to reach rebel-held parts of the city where some 250,000 people live, even though aid delivery was part of the U.S.-Russia truce agreement.

The Britain-based Syrian Observa- tory for Human Rights said at least 27 civilians, including three children, were killed in dozens of raids that began overnight. A member of the city’s forensic team, Mohammed Abu Jaafar, said he had documented 54 deaths since late Thursday.

The pressure on rebel-held parts of the city is the most serious in years now that all areas are surrounded by government forces and their allies, including Iraqi fighters and militants from Lebanon’s Hezbollah group.