More than 600,000 homes in the north-eastern United States are without power as a snowstorm continues for a second day.
A nuclear power station in Massachusetts shut down as five states along the east coast declared a state of emergency.
Blizzard warnings are in effect from Newark, New Jersey to southern Maine. Many areas are under two feet of snow and more is expected - as much as three feet in some places.
The storm began on Friday. The BBC reports millions of people have been told to stay indoors and almost all flights have been cancelled.
Massachusetts Governor Deval Patrick has banned all non-essential traffic.
People have been warned to stock up on food and other supplies as the storm affects 25 million people in the region.
The National Weather Service said two weather systems from the polar and sub-tropical jet streams have combined.
In Canada, New Brunswick, Nova Scotia and Newfoundland are also under blizzard conditions.
CBC reported Ontario has already seen 200 vehicle accidents. At least three people have been killed.