Drone footage obtained by Reuters shows extensive damage in eastern Aleppo, since the breakdown of a ceasefire in Syria last week.
The footage shows collapsed buildings, near-deserted streets and enormous water-filled craters.
The one-week truce in the country ended last Monday (September 19) when an aid convoy was hit by an air strike.
Since then, rebel-held eastern Aleppo has come under heavy bombardment.
Some 250,000 civilians remain trapped in the besieged, opposition-held sector of Syria's biggest city. Hundreds of people, including dozens of children, have been reported killed since last Thursday night (September 22) by an onslaught that includes bunker-busting bombs that bring down whole buildings.
The Syrian government offensive to recapture all of Aleppo, with Russian air support and Iranian help on the ground, has been accompanied by bombing that residents describe as unprecedented in its ferocity.
In a tense confrontation at the United Nations over the weekend, the United States called Russia's bombing in support of Assad "barbarism", and said Russia was killing civilians, medical staff and aid workers.
