The raging forest fires in Canada's Alberta province showed some signs of receding on Sunday, as favourable weather helped firefighters and winds took the flames southeast, away from oil sands boomtown Fort McMurray.
But the 88,000 inhabitants of Fort McMurrey who escaped the fury of the forests, may have to wait to come back to normalcy and energy companies may take time to restart oil extraction.
The massive wildfires in the Alberta province in western Canada that had doubled in size to more than 2,000 sq km by Sunday as the shifting winds pushed wildfires away from the already ravaged oil sands of Alberta to the heavily forested areas in the northeast, had already cut Canada's vast oil sands output by half.
Thick, heavy smoke blanketed large areas of British Columbia, where firefighters battled 89 new wildfires across the province, and spread across the border to the US West, prodding health advisories, Canadian officials said.
The new fires, all of which started on Friday, brought to 184 the number of active blazes across the western province, the BC ministry of forests, lands and natural resources operations said on Monday.
The Alberta government said on Saturday the massive blaze in the province will cover more than 2,000sq km by Sunday and continue to grow because of high temperatures, dry conditions and high winds.
Chad Morrison, Alberta's manager of wildfire prevention, said what troubled the administration was the possibility of the growing wildfire further doubling in size to reach a major oil sands mine and even the neighbouring province of Saskatchewan.
Canada's minister of public safety Ralph Goodale called the Fort McMurray blaze ''an absolute beast of a fire,'' and one of the worst he's ever seen, the Edmonton Journal reported.
Nearly 90,000 people have been evacuated from the area in the heart of Canada's oil sands region, with some forced to relocate twice as the flames shifted.
The fire so far has destroyed about 1,600 buildings and homes. The mass evacuations forced as much as a quarter of Canada's oil output offline. The region contains the third-largest reserves of oil in the world, behind Saudi Arabia and Venezuela.
Alberta's government estimated on Sunday that the fire had consumed 161,000 hectares (395,000 acres). That was less than a previous estimate, but authorities warned the fire would likely grow overnight.
Fort McMurray is the center of Canada's oil sands region. About half of the crude output from the sands, or 1 million barrels per day, has been taken offline, according to a Reuters estimate.
Oil prices jumped almost 2 per cent in trading early on Monday, as Canada's fire contributed to tightening supply.