A state of emergency has been declared in the Canadian city of Fort McMurray as a massive blaze prompted the biggest evacuation in the history of Alberta state. 

Officials warned on Wednesday that the fire had the potential to destroy much of the town with a few neighbourhoods already destroyed.

Wind-whipped wildfires, which broke out on Sunday, have destroyed at least 1,600 homes and other buildings and forced more than 80,000 residents to flee.

Danielle Larivee, Alberta's minister of municipal affairs, said the fire was actively burning in residential areas, with more than 250 firefighters battling the blaze.


READ MORE: Wildfire forces evacuation of Canada's Fort McMurray


An update from the Municipality of Wood Buffalo later in the evening indicated that the fire was continuing to claim homes and had destroyed a new school.

Authorities said there had been no known casualties from the blaze itself, but deaths were reported in at least one car crash when people were evacuating.

Chelsie Klassen, a spokeswoman for the Canadian Association of Petroleum Producers, said all large oil sands facilities would be properly shut to minimise the damage. 

'Heartbreaking'

Alberta Premier Rachel Notley flew up to survey the situation, while officials in the evacuation centre had to bolt to the south of the city as flames edged closer.

Notley tweeted pictures of the fire from above. "The view from the air is heartbreaking," she wrote.

Notley said about 10,000 evacuees moved north where oil sands work camps were being pressed into service to house evacuees. The bulk of the evacuees fled south to Edmonton and elsewhere, and officials said they eventually would like to move everyone south.

Canadian Prime Minister Justin Trudeau said, while the full extent of the damage wasn't yet known, that it was "absolutely devastating" and that there was loss on a scale that was hard to imagine.

Trudeau said he had offered the province his government's full support. 


WATCH: Playing with fire


Fort McMurray is surrounded by wilderness in the heart of Canada's oil sands - the third largest reserves of oil in the world behind Saudi Arabia and Venezuela.

It was the second major blaze in the oil sands region in a year. Last May, wildfires led to the evacuation of hundreds of workers from the region, and a 9 percent cut in Alberta's oil sands output.

Source: Agencies