A bicyclist rides under a canopy of trees coated with ice from a winter storm in Hinsdale, Mass., Friday. (Ben Garver/Berkshire Eagle/Associated Press)

A massive ice storm roared into the northeast United States Friday, toppling trees, closing schools and leaving more than 1.25 million homes and businesses without power.

The storm hit seven states, striking New Hampshire, Massachusetts, Maine and New York the hardest. State of emergencies were declared in New Hampshire and Massachusetts, as authorities anticipated that it could be several days before power could be restored.

In New Hampshire alone, more than 400,000 hydro customers were without power, meaning more than half the state was in darkness. By comparison, only 55,000 customers in New Hampshire lost power during the 1998 ice storm.

Traffic is redirected in Derry, N.H., after a utility pole snapped due to an overnight ice storm Friday. (Cheryl Senter/Associated Press)

"This is the absolute, most significant power restoration effort we've ever had. There has not been a storm before that has affected more customers," said Martin Murray, spokesman for the state's largest utility, Public Service Company of New Hampshire.

At least one death is attributed to the storm. A man in Danville, a town in southeast New Hampshire, died of carbon monoxide poisoning after he turned on a generator in his trailer because the power had gone out, police said.

Nearly two dozen temporary shelters were set up across the state to house those without heat and power, while authorities were scrambling to set up generators in nursing homes.

Check on neighbours, governor urges

New Hampshire Gov. John Lynch urged residents to check on their neighbours, especially the elderly.

In Massachusetts, 500 members of the National Guard were dispatched to clean up debris, while the Red Cross set up 23 emergency shelters.

"All of the resources at our disposal have been made available to try to get the roads clear and power restored," said Gov. Deval Patrick, adding that it could be a long time before power is restored.

"This is not going to be a couple of hours," Patrick said. "It's likely to be several days."

Hydro crews from as far as Maryland and Ohio were being called in to help do repairs in powerless communities. Canadian teams were also assisting.

Storm sweeps Canada

Meanwhile, Canadians were coping with their own stormy weather Friday.

In central and southern Alberta, a snowstorm forced airlines to cancel flights, reduced visibility on roads and slowed city traffic to a crawl. Up to 20 centimetres of snow was expected in the Calgary area by Saturday, with winds gusting to 60 km/h and temperatures plunging to -30 C.

Snowstorms also roared into Quebec earlier Friday, with Environment Canada issuing weather warnings for more than 40 areas across the province earlier Friday. Transport officials warned drivers to be cautious because of heavy snow.

Nova Scotia and New Brunswick were coping with large power outages after snow, rain, freezing rain and high winds struck Friday.

Snow warnings were issued Friday night for southern Saskatchewan, eastern Labrador and southern B.C.