Ambulances lined up outside Wainwright Health Centre after the deadly blast at Canadian Forces Base Wainwright

Several people have been killed or injured as a result of a large fire near a Canadian military base in Alberta, the nation's defence minister has said.

David McGuinty did not confirm the cause or the number of casualties, describing the situation as "very, very active and delicate". The Canadian military and local authorities were managing the fire, he said.

Canadian Forces Base Wainwright, where the fire broke out, is one of the country's busiest military training bases.

Canadian TV network Global News reported that at least seven were killed and dozens more injured when a gas line or gas well was hit during a live-fire training exercise, citing unnamed military sources.

Canada's Prime Minister Mark Carney said that a "serious incident creating a major fire" had occurred, adding that his "thoughts are with all the brave women and men affected".

The Canadian Broadcasting Corporation (CBC) said Royal Alexandra Hospital in Edmonton had declared a code orange, a disaster response protocol for responding to a high-casualty incident.

Warren Thirsk, an emergency department doctor there, told the broadcaster that the number of patients would otherwise "overwhelm" Edmonton's healthcare facilities.

"It is more patients than any of us want to count right now. It's a disaster. It's a one in every 15 to 25-year disaster."

After the fire erupted on Saturday, it "spread rapidly due to high winds" and tore through the fences of the base, the Municipal District of Wainwright said.

The region experienced gusts of up to 100km/h (62mph), though local officials indicated fire crews had contained the blaze.

The defence minister told reporters he "cannot recall an incident like this in recent memory".

It is unclear when the fire broke out, but the district first posted about the incident at about 17:30 local time (23:30 GMT).

Local authorities have urged residents to avoid the area and give all emergency vehicles right of way.

The mayor of the nearby town of Wainwright, Bruce Pugh, said it was a "heavy day" for his community.

"We have neighbours who are either serving or former members of the Canadian Armed Forces. We're integrated, our kids play in the same hockey teams, attend the same schools," he told CBC.

While details on the impact of the fire remain unclear, Pugh said he believed this would come to be the area's largest-ever mass casualty event.

Canadian Forces Base Wainwright is a busy military training base used for live-fire exercises

Alberta's Premier Danielle Smith said the "significant and tragic fire" was "affecting many of [the province's] brave military personnel".

Neighbouring provinces have mobilised in support. Saskatchewan Premier Scott Moe said he had deployed resources to Alberta and was "ready to provide more if required", while British Columbia Premier David Eby said his government had offered "all possible assistance".

Wainwright is the main base used by the Canadian military for live-fire training exercises, according to CBC, with about 690 military personnel and 300 civilian workers on-site on a typical day.