Syrian government forces gather in the largely deserted Palestinian refugee camp of Handarat, north of Aleppo, on Sept. 24, after they captured the area following multiple Russian airstrikes. (George Ourfalian/AFP/Getty Images)

Syrian and Russian warplanes launched a fresh blitz on Aleppo on Saturday as government troops pressed a major offensive to take back the city.

In the rebel-held eastern suburbs, residents said scores of civilians had been killed or injured, pushing doctors to work 24-hour shifts and treat patients on bloodied floors when beds ran out.

The attacks — ongoing since Monday — have shredded a cease-fire deal hailed by the United States and Russia as a rare chance to push the war toward peace talks and its eventual conclusion.

In its place are bombs, raining down with a ferocity unseen during five years of war.

A provisional death toll provided by local nongovernmental organizations on Saturday suggested that at least 92 people had been killed in the eastern suburbs since dawn.

“We did not sleep,” said Omair Omar, a young journalism student from Aleppo. As warplanes droned overhead, his room filled with the flash and rumble of several explosions.

For Syrian President Bashar al-Assad, the city represents an important prize that would expand government control in the north and deprive opposition groups of one of their last main strongholds.

East Aleppo’s population of 275,000 has been under near-continuous siege since government troops encircled the area in mid-July.

On Saturday, government troops dueled with rebels for control of Handarat, a Palestinian refugee camp that sits on high ground overlooking a main road into Aleppo. Assad’s forces moved on the site in the early morning, marking the first major advance in an offensive heralded as an attempt to take back the city.

Speaking at the U.N. General Assembly in New York, Syria’s top diplomat, Walid al-Moallem, told gathered leaders that his government’s belief in military victory was being strengthened by its “great strides in the war against terrorism.”

But activists said this past week’s airstrikes focused squarely on crippling what limited resources the crumbling suburbs have left. Among the targets, they say, have been operational hubs for the civil defense group known as the White Helmets, whose teams rush to bombing sites to aid survivors.

The latest cease-fire in Syria lasted only six days before the warplanes returned to the skies above Aleppo. Eyewitness accounts claim that white phosphorus munitions were dropped on the city on September 20. The incendiary weapon burns at extreme temperatures. (TWP)

In a statement Saturday, U.N. Secretary General Ban Ki-moon described the escalation as “chilling” and said the apparent systematic use of incendiary weapons and bunker buster bombs may amount to war crimes.

UNICEF, the U.N. children’s agency, also warned that intensified attacks had left nearly 2 million people without access to clean water, posing serious risks to a population mostly reliant on highly contaminated wells.

“It is critical for children’s survival that all parties to the conflict stop attacks on water infrastructure,” it said in a statement. Wissam Zarqa, an English teacher, said his own Aleppo neighborhood was lucky to receive water every 15 days.

As the United States and Russia scrabbled Saturday to revive the cease-fire, Syria’s chief opposition coordinator, Riyad Hijab, told reporters there was “no longer any use” for such partial truces. “I know there is no Plan B, and that is why we are demanding the U.S. to do something and let there be a Plan B,” he said.