Video report by ITV News Correspondent Neil Connery
At least 91 people died in rebel-held eastern districts of Aleppo on Friday in the second day of intense bombings described by an expert as "nothing short of Armageddon".
Weapons expert Hamish de Bretton-Gordon told ITV News that cluster munitions, incendiary devices - all illegal under international law - and bunker busting bombs have targeted hospitals for women and children.
The Syrian government said the bombardment was part of a new offensive in eastern Aleppo that might go on "for some time" but insisted forces are targeting "terrorist positions and gatherings" and not civilians.
Mr de Bretton-Gordon said the offensive is reminiscent of Stalingrad in World War Two.
"There appears to be a scorched earth policy with absolutely no regard for human life with the aim being to raze eastern Aleppo to the ground until everybody is dead or left Aleppo," he said.
"The story is reminiscent of Stalingrad in World War Two, and the Russians would do well to consider the 'shock' of Stalingrad on the Russian character, as they enable the Syrian Regime to repeat this in Aleppo."
Muhammad Ali Halabi, whose home in Aleppo was attacked, saw his neighbours' six-storey buildings collapse and the families inside killed.
He told ITV News he believes a more powerful weapon appears to be being used against citizens in Aleppo: "Our neighbourhood was violently targeted by a missile, I noticed a new kind of missile...
"The Russians are using new kinds of weapons."
The Syrian Observatory for Human rights said there were at least 40 airstrikes since midnight.
Dramatic images have emerged of young children and babies injured in the aerial bombings.
In one video, civil defence workers are seen frantically digging and untangling a baby boy from debris after a strike in Kafr Hamra.
WARNING: Some viewers may find the below video upsetting
A local professor, Abdulkafi Alhamdo, told ITV News: "People now they are dying of extermination, real genocide, 3,000,000 Syrians in danger are in danger of extermination. The world should know and be so sorry for letting us down."
US Secretary of State John Kerry and Russian counterpart Sergey Lavrov clashed at the UN on Wednesday over the failed Syria ceasefire.
Kerry blamed Russia for an attack on an aid convoy which killed 20 civilians but Moscow denied any involvement.
He accused Lavrov of "shredded any hopes of a ceasefire" but on Friday he said that a little progress had been made.