Mike Ellis, Alberta's minister for public safety, says the fire was 5km (3 miles) outside of Jasper when it was pushed by a powerful wind gust to the town in "less than 30 minutes".

"Any firefighter will tell you there is little to nothing you can do when you have a wall of flames coming at you like that," he says.

"Nobody anticipated that fire to come so fast, so large and so quickly."

While the extent of the devastation remains unclear, Premier Danielle Smith says that 30% to 50% of the buildings in the town of Jasper in Alberta have potentially suffered damage.

Officials add that the focus right now is on protecting critical structures in the town.

That work, they say, is being done by structural firefighters from around Alberta who are now assisting efforts in Jasper.

The wildfire that scorched Jasper, destroying parts of the city and the national park, was "uncontrollable", an official tells the news conference.

"Due to the wind gusts, that brought the fire up to about 100m (328ft) high at one point and covered an inordinate amount of space in a very little amount of time," the official adds.

Image source, Alberta Government

It's unclear how much infrastructure has been affected because the wildfires are ongoing, Alberta premier Smith says.

"We haven't had a line of sight," she says.

She notes that officials have seen images shared on social media showing infrastructure damage but adds that she doesn't know much beyond that.

An Alberta wildfire official says there were reports of rain "on and off" overnight in the area of the wildfires.

She says the rain slowed the fire somewhat but added "it really was not sufficient to make a humongous change".

"This is still obviously a long-term fire fight, for now," she says.

At least 400 firefighters from around the world are joining the effort to help fight the Jasper fires in the coming days, an Alberta wildfire official says at the news conference.

One hundred firefighters from Jalisco, Mexico, are arriving in Jasper today, 200 from South Africa will arrive tomorrow and another 100 will be there to help on Sunday and Monday, from Australia and New Zealand.

Jasper is a tourist town in Alberta, Canada and has a population of about 4,100 people.

It is part of the historic Jasper National Park.

The out-of-control wildfires which hit the region led to some 25,000 people being evacuated from the park.

Image source, Alberta government

Minister of Forestry and Parks Todd Loewen is speaking now. He's explaining the extent of support needed to fight the wildfires.

Firefighters, support personnel, water trucks, a dozer group, helicopters and airtankers have all been sent to help fight the blaze, Loewen says.

Alberta's government is also sending an incident management team to help assess the situation, he adds.

Image source, Alberta government

An evacuation order has been issued for residents in the town of Jasper in Alberta, Canada.

Roughly 25,000 people have evacuated from historic Jasper National Park, Alberta official Mike Ellis tell the news conference.

At the time of the evacuation order, the "vast majority" of these people were visitors, he adds.

"We will recover from this... and to all those around the world, the magic is not lost of Jasper," Smith says.

She adds that the situation on the ground overnight in Alberta was "extremely volatile".

She says the government will work to rebuild stronger so future generations can continue to experience this "one of a kind community".

Alberta Premier Danielle Smith offers a brief update on the current situation in Jasper.

She says the wildfire is still out of control and crews are working in dangerous conditions to try to protect critical infrastructure in the town.

Image source, Alberta government

Alberta Premier Danielle Smith has begun speaking. She is crying from the podium as describes the damage from the Jasper wildfires.

"This is the worst nightmare for any community," she says.

She continuously has to pause her remarks to push through tears.

In a statement earlier today, Jasper's mayor Richard Ireland spoke candidly about the devastation suffered in his town as a result of the wildfires.

He says he is filled with "profound sorrow" as he and the community start to come to terms with the loss, which he says is "beyond description and comprehension".

"This experience is tremendously traumatic for each of us and for the community," he adds.

In a tearful interview with CBC News yesterday, he called the fire his community's "worst nightmare".

At the time, he said he received word of multiple structures that had burned down in his community.

"It appears that the damage will be extensive," he said. "Like all residents, I feel devastated, shattered and absolutely helpless in the face of nature, which is just so powerful."

Image source, Alberta Wildfire/Handout via REUTERS

Thousands of people have fled the Canadian tourist town of Jasper since wildfires began burning earlier this week.

Park officials at the Jasper National Park said the blaze has caused "significant loss" within the town.

Personnel from Alberta - including 1,900 firefighters - Alaska and Australia have been deployed to help fight the fires.

Forecasters say rain today will offer a brief reprieve from the flames - which were made worse by dry and hot weather in recent days.

The extent of the damage remains unclear, but we're hoping officials will provide more information at this afternoon's news conference.

You can watch the update on the Alberta wildfires live by clicking Watch live at the top of this page.

We'll bring you live text updates here too.

We're about to hear from officials in Alberta about the latest on wildfires in the Canadian tourist town of Jasper.

Earlier this week, 25,000 people were forced to evacuate the historic resort and the latest images shows widespread damage.

Stay with us for live updates.