At least 28 people have died in western New York state, most in Buffalo, and 56 in total as a monster winter storm continues to batter North America.
A state official said some people had been trapped in cars for more than two days during what was "probably" the worst storm of their lifetime.
Up to nine more inches (23cm) of snow are expected in parts of the state on Tuesday, meteorologists warn.
The storm has stretched from Canada to Mexico.
US President Joe Biden approved an emergency declaration allowing federal support for New York State. "My heart is with those who lost loved ones this holiday weekend," he tweeted.
Neighbouring state New Jersey also sent emergency services to New York state to provide further assistance.
State Governor Kathy Hochul, a native of Buffalo, described the storm as "the blizzard of the century".
"It is [like] going to a war zone, and the vehicles along the sides of the roads are shocking."
She added that many emergency vehicles had been unable to reach worst-hit areas or had got stuck in snow themselves.
They fled south to escape winter. The storm still found themHow to stay safe in a winter storm
New York state officials said emergency personnel were going from car to car searching for survivors of the storm, and finding bodies in cars and snow banks.
Mark Poloncarz, executive of Erie County where Buffalo is located, said others died from cardiac arrest while ploughing snow, with Buffalo state issuing a "Shovel Smart" warning, notifying people that over-exertion from shovelling snow can cause heart attacks or back injuries.
One local family with young children - aged two to six - had to wait for 11 hours before being rescued in the early hours of Christmas Day (Sunday).
"I was basically just hopeless," the father, Zila Santiago, told CBS News. He said he managed to stay warm by keeping the engine running, and kept distress at bay by playing games with the children.
Ditjak Ilunga from Gaithersburg, Maryland, told CBS News he was on his way to visit relatives in Hamilton, Ontario, with his daughters when their SUV was trapped in Buffalo.
After spending hours with the engine running he made the desperate choice to risk the howling storm to reach a nearby shelter.
He carried six-year-old Destiny on his back while 16-year-old Cindy clutched their Pomeranian puppy, and followed his footprints in the snow drifts.
"If I stay in this car I'm going to die here with my kids," Mr Ilunga recalled thinking.
He said he cried when the family walked through the shelter doors. "It's something I will never forget in my life," he said.
Meanwhile, the owner of a small family-run shop in East Buffalo, who didn't want to be named, said looters broke into his general store on Christmas Day.
"They took everything. People took toys, electronics and speakers," he said.
He estimated up to $50,000 (£41,000) worth of equipment was stolen. He said he called the police, "but they told me they were too busy rescuing the elderly".