More than 500,000 households in the north-eastern United States and south-eastern Canada are still without electricity after severe ice storm last weekend.
Despite crews working round-the-clock, some houses could be without power at least until Saturday.
In Toronto, 72,000 people were without electricity on Christmas Day. The BBC reprots at least 27 deaths in the region have been linked to the storm.
Most of those were caused by apparent carbon monoxide poisoning due to gas generators, charcoal stoves and other appliances being used to heat houses in freezing temperatures.
"I understand they want to keep warm, but you cannot do this. This is deadly," Toronto Mayor Rob Ford warned earlier this week.
Other fatalities were caused by traffic accidents.
Elsewhere in Canada, people are still without power in New Brunswick, Quebec and Nova Scotia.
In the United States, states from Maine to Michigan have been affected by the weather.
The BBC reports travel between Toronto and Montreal, Ottawa and New York is disrupted.