The four Canadian soldiers who died during a training exercise at the weekend did so when a grass fire spread "a kilometre in 36 seconds", officials said.
Military personnel said 39 people were in hospital after the fire at Canadian Forces Base Wainwright on Saturday.
Sergeant Morgan Wong, of the Loyal Edmonton Regiment, and Privates Shaun Farrell, Aidan Goulding and Hayden Lykkemark of the 3rd Battalion, Princess Patricia's Canadian Light Infantry were killed.
All four had been serving with the battalion, based in Edmonton.
Alberta premier Danielle Smith said 19 of the injured are in a critical condition, while many will require "weeks and months" of specialised, intensive medical care.
The King, who is monarch of Canada, said in a message of condolence that he and the Queen were "greatly shocked and saddened".
"Our deepest sympathy and heartfelt condolences are with the families and loved ones of those who have lost their lives, and with all those who have been injured or otherwise affected at this most difficult time," he wrote.
Military base fire - as it happened
Canadian prime minister Mark Carney described the incident as one of the worst peacetime tragedies for Canada's military on home soil.
Flags on federal buildings across the country will be lowered to honour the victims, he added.
Some 85 soldiers were carrying out "high intensity" combat training using live munitions when the grass fire started at around 4pm local time.
The soldiers were preparing for deployment to Latvia, where Canadian forces currently have their largest international military operation.
Major General Wade Rutland said military officials were aware of the blaze for hours and thought it was contained.
However, he said the area was experiencing high winds and gusts of up to 60mph at the time, sending flames racing toward the soldiers.
He added: "The fire was a kilometre away when the wind shifted. That is not normal for a fire to move a kilometre in 36 seconds.
"I've certainly never seen anything like it."
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Rutland said the incident remains under investigation and declined to speculate on what caused the grass fire.
He said officials do not believe the region's extensive oil and gas infrastructure had anything to do with the incident, while "outside interference" has also been ruled out.
(c) Sky News 2026: Four Canadian soldiers killed after grass fire spread 'a kilometre in 36 seconds'


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