Shocking new footage shows just how bad the bombings have got in the rebel-held districts of Aleppo. This comes as part of the Syrian government's new offensive on the city.
The intense bombing was renewed when diplomatic efforts failed to salvage a ceasefire that lasted nearly a week.
Residents and activists said the bombing, which began in earnest late on Wednesday, has been unprecedented, targeting residential areas, infrastructure and the award-winning volunteer civil defence group known as the White Helmets.
The Britain-based Syrian Observatory for Human Rights said at least 27 civilians, including three children, were killed in about 30 raids that began overnight.
A Syrian military official said air strikes and shelling in Aleppo might continue for an extended period, and the operation will expand into a ground invasion of rebel-held districts.
After a contentious two-and-a-half hour meeting with colleagues in New York, US secretary of state John Kerry and Russian foreign minister Sergey Lavrov said they would meet again on Friday in a bid to find a way forward.
Despite a week of diplomatic talks and attempts to seek consensus, developments on the ground in Syria seem to have overshadowed prospects for bringing about calm.