A Canadian official has said that a massive wildfire going on in the state of Alberta is likely to double in size, as evacuation efforts continue in the fire-ravaged oil city of Fort McMurray.

Canadian police led convoys of cars through the burning ghost town of Fort McMurray on Friday in a risky operation to get thousands of people to safety.

A day after 8,000 people left the oil city, authorities said 5,500 more were expected to leave their homes by the end of Friday and another 4,000 on Saturday.

More than 80,000 people have left the city in the heart of Canada' oil sands, where the fire has torched 1,600 homes and other buildings, according to the Associated Press news agency quoting officials.


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


Chad Morrison, Alberta's manager of wildfire prevention, said there was a "high potential that the fire could double in size" by the end of Saturday.

He expected the fire to expand into a more remote forested area northeast and away from Fort McMurray, according to the AP.

Extremely dry conditions and a hot temperature of 27 Celsius was foreseen on Saturday along with strong winds, he said.

Morrison said no amount of resources would put this fire out, and what was needed was rain.

"We have not seen rain in this area for the last two months of significance," Morrison said. "This fire will continue to burn for a very long time until we see some significant rain."

Environment Canada forecast a 40 percent chance of showers in the area on Sunday and Morrison said cooler conditions were expected Sunday and Monday.

State of emergency

The mass evacuation forced as much as a quarter of Canada's oil output offline and is expected to impact a country already hurt by a dramatic fall in the price of oil.

The Alberta provincial government, which declared a state of emergency, said on Friday that the size of the blaze had grown to about 1,000 square kilometres.

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 fleeing the fire.

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

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.

Source: Agencies