A fast-moving grass fire that killed at least four soldiers at a western Canadian military base on Saturday was sparked by an exercise using live grenades, a senior defense official said on Thursday.
High winds then propelled the blaze across the army base in Wainwright, overwhelming dozens of soldiers. The incident was one of the worst peacetime tragedies for Canada's military.
"The fire initiated on the automatic grenade launcher range ... (it) initiated as a result of routine military training that was happening on that range at the time," Brigadier-General Vanessa Hanrahan told reporters.
Officials said 27 people remain hospitalised, several in critical condition. The soldiers and reserve members were preparing to deploy to Latvia, where Canadian forces have their largest international military operation.

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