Canada announced Wednesday the first H5N1 avian flu death in North America, of a patient who had just returned from China, and said it was urgently contacting airline passengers on the victim's flights.

It was also the first known instance of someone in North America contracting the illness, Canada Health Minister Rona Ambrose told a press conference, stressing it was an "isolated case."

A blast of bone-chilling cold reaching lows not seen in two decades gripped the United States early Tuesday, snarling air travel, closing schools and prompting calls for people to stay inside.

Superlatives of cold-talk abounded, even in midwestern states used to chest-high snow and bitter cold, as the National Weather Service said the deep freeze was making its way east.

Extreme cold in Canada Monday disrupted flights and school classes, caused widespread power outages and created havoc on roads.

Temperatures as low as minus 50 degrees Celsius (-58 Fahrenheit) with a wind chill -- colder than the surface of Mars -- plunged the western Prairies region into a deep freeze, heightening risks of frostbite and hypothermia.

A fierce winter storm has caused chaos in the United States since the start of the year, killing 11 people, canceling thousands of flights and bringing freezing temperatures to Canada.

Northeastern U.S. states felt the biggest impact, with more than 24 inches (61 centimeters) of snow falling in parts of a Massachusetts town and a state of emergency being declared in New York and New Jersey.

An H1N1 flu outbreak in Alberta has sickened nearly 1,000 people and killed five, the Canadian province's health minister said Friday, urging everyone to get vaccinated.

"Over the past few weeks, we have seen a surge in the number of influenza cases across Alberta. Many of those affected are healthy young adults," Health Minister Fred Horne said in a statement.

A Canadian lawmaker said Thursday she was intimidated and warned she could be deported during an ongoing visit to her birthplace of Jaffna, the war-battered Tamil heartland of Sri Lanka.

Rathika Sitsabaiesan, an ethnic Tamil, was subjected to "political intimidation" and warned of possible arrest and deportation, according to a statement on her New Democratic Party's (NDP) website.

Utility crews from Maine to Michigan and into Canada worked to restore power to more than half a million homes that were left in the dark by last weekend's ice storm, which has been linked to 27 deaths.

In the United States, the death toll from the storm reached at least 17 on Christmas day, from traffic accidents and carbon monoxide fatalities.

Canada's Supreme Court on Friday struck down key portions of a law that effectively criminalized prostitution by banning brothels and soliciting on the streets, declaring this disproportionate.

But it stayed its unanimous nine to zero ruling for one year to allow Parliament to consider whether or not impose other limits on where and how prostitution may be conducted.

Canada is expected to file an application with the United Nations on Friday seeking to vastly expand its Arctic sea boundary, setting it on a collision course with Russia and Denmark.

Orders from the prime minister to eventually also include the North Pole in the claim, revealed in a recent news report, is expected to rankle Moscow and Copenhagen, which also have their eyes on the region.

Beijing on Monday dismissed as "groundless" allegations that a Canadian naval engineer is a Chinese spy.

Qing Quentin Huang, 53, was charged at the weekend under Canada's Security of Information Act with two counts of attempting to communicate classified information to a foreign entity.