Pallade Veneta - Wildfire engulfs parts of main town in Canada's Jasper National Park

While the fire has so far caused no casualties, as many as 25,000 residents and tourists were evacuated from the area before the conflagration suddenly grew in size, overtaking firefighters.

"There is no denying that this is the worst nightmare for any community," said Danielle Smith, Alberta province's premier, adding that damage to the town was estimated at between "30 to 50 percent."

Prime Minister Justin Trudeau called images of the damage "heartbreaking," and said his government had asked more than 400 firefighters from Australia, New Zealand, Mexico and South Africa to aid local authorities.

"Thank you for your courage, and for working non-stop to fight these wildfires," he said in a post on social media platform X.

A video circulating on social media showed the city of Jasper's streets covered in ash, with cars turned to charred carcasses and buildings reduced to rubble.

Mayor Richard Ireland wrote in an online post of a sense of destruction and loss that was "beyond description and comprehension."

On Thursday, firefighters were still hard at work in the town, with much-anticipated rain having "no significant impact" on the blaze, according to Jasper National Park authorities.

"Jasper National Park received a small amount of rain overnight. While the rain helped reduce fire activity slightly, it is not enough to have made a meaningful impact to the overall wildfire situation, which remains out of control," read a post on the park's X account.

In places, the flames reached a height of 120 meters (390 feet) and were moving at a speed of 15 meters per minute.

The fire entered the deserted town on Wednesday evening after advancing very rapidly late in the day, pushed by strong winds in a region hit by severe drought and which has seen record heat in recent days.

Jasper National Park, Canada's largest, is known for its mountains, glaciers, lakes and waterfalls, and attracts 2.5 million visitors every year.

- 'Devastation' -

"Everyone has a total feeling of devastation," said Pattie Pavlov, a Jasper resident who drove for hours on Monday night to escape the advancing fire.

"Many people are feeling very helpless. Because there's nothing that we can do."

The general manager of the Jasper Park Chamber of Commerce said she had taken refuge with friends more than 500 kilometers (310 miles) away from her home.

In tears, Alberta Premier Smith provided an assessment of the damage and recalled that "for many generations" the town and Jasper National Park were "a source of pride."

In recent days, numerous fires have been started by lightning in western Canada.

In Alberta province, more than 170 fires were active on Thursday, including more than a dozen in the Fort McMurray region, a hub of oil sands development.

British Columbia, Alberta's neighboring province, was grappling with 400 active fires, more than half of which were burning out of control.

Fifty-six fires have started in the last 24 hours alone, authorities said.

O.Mucciarone--PV