Syria in all-out assault to retake Aleppo
SYRIAN government forces have made their first all-out ground assault to retake Aleppo, making their deepest push into rebel-held areas since the war began.
Troops retook a central district from rebels as they attacked from four fronts on Monday, in their first such offensive inside the city since the opposition took hold in 2012.
They advanced towards the contested old quarter of Aleppo - home to the Umayyad Mosque, a Unesco world heritage site.
There was also fierce fighting to the south, where rebels are battling pro-government troops to reopen the only route out for the some 250,000 residents trapped on the eastern side.
Syrian and Russian warplanes have been bombing east Aleppo with an unprecedented ferocity over the past five days, killing more than 350 people.
Doctors say hospitals are overwhelmed and running out of supplies. Save the Children said operations were being conducted without anaesthetic.
A ceasefire brokered by the US and Russia, billed as Syria's "last chance", collapsed last week amid recriminations and accusations of violations from both sides. As it crumbled, Russia threw its military might behind the Syrian regime's drive to regain Aleppo.
Once Syria's industrial hub, Aleppo is so important to both sides that it is said whoever takes it, wins the war. A Western diplomat said with neither side strong enough, there could be a year of street-to-street fighting. "The only way to take eastern Aleppo is by such a monstrous atrocity it would resonate for generations," he said.
President Bashar al-Assad's Syrian army, which is thought to number about 15-20,000 around Aleppo, is bolstered by tens of thousands of troops from Russia, Iran and Iraq, as well as by Shia militias.
There are estimated to be a similar number of opposition fighters.