A major fire broke out Saturday in a training area at Canadian Forces Base Wainwright in Alberta, killing and injuring an undetermined number of people, Defence Minister David McGuinty said. The Royal Canadian Mounted Police said officers were called shortly after 4 p.m. following reports of a fire at the base. Strong winds, with gusts of up to 100 kilometres an hour, spread the flames through the base's fences and into the surrounding rural area, according to the Municipal District of Wainwright.

McGuinty did not confirm a cause or casualty figures, describing the situation as "very, very active and delicate" and saying it would soon become "an active and delicate investigation." He said the RCMP were involved and that he could not recall a comparable incident in recent memory. Global News, citing unnamed military sources, reported that at least seven people were killed and dozens injured when a gas line or gas well was hit during a live-fire training exercise. That account has not been confirmed by officials.

Hospitals in the region faced intense strain. Dr. Warren Thirsk, an emergency physician at the Royal Alexandra Hospital in Edmonton, about 120 miles northwest of the base, told CBC News that health-care facilities near the base had become "completely overwhelmed" and that patients were being brought to hospitals across Edmonton. He called the event "a one in every 15 to 25-year disaster." CBC reported that the hospital declared a code orange, the protocol for a high-casualty incident.

By 11 p.m., the Municipal District of Wainwright said the fire was being held and that property and critical infrastructure were protected. No evacuation order was issued for residents, though people were urged to avoid the area and yield to emergency vehicles. Prime Minister Mark Carney cited a "serious incident creating a major fire" and said his thoughts were with those affected. Alberta Premier Danielle Smith called the fire "significant and tragic" and said it was affecting many military personnel. Saskatchewan Premier Scott Moe said his province had sent assistance, and British Columbia Premier David Eby offered "all possible assistance."

CFB Wainwright is one of Canada's busiest military training bases and the main site for the Canadian military's live-fire exercises. It is home to the Canadian Manoeuvre Training Centre, and about 690 military personnel and 300 civilian workers are on site on a typical day. Wainwright Mayor Bruce Pugh said the town's residents are closely tied to the base, with many neighbours serving or former members of the Armed Forces, and he said he believed the event would become the area's largest-ever mass casualty event. Officials said more information on the casualties and the cause would be released in the coming hours and days as the investigation proceeds.