Four military members are dead and dozens more have been seriously injured after an explosion and fast-moving fire at Canadian Forces Base Wainwright in Alberta, in what Prime Minister Mark Carney described as one of the worst tragedies to hit the Canadian Armed Forces during peacetime. Thirty-nine people were hospitalized, 19 of them in are in critical condition. The incident occurred at about 4 p.m. local time Saturday at the military base east of Edmonton. Emergency crews rushed to the scene as the fire spread rapidly, prompting a major medical response across the region. The Canadian Armed Forces says it is still assessing the full extent of the impact. Here is what we know so far: Four military members killed, dozens injured Prime Minister Mark Carney confirmed the deaths and injuries Sunday. Family members of those killed have been notified, Carney said. Those affected included personnel from military bases across the country, including reservists and soldiers serving with Princess Patricia’s Canadian Light Infantry. In his remarks on Sunday, Carney described the scale of the tragedy. “Yesterday afternoon, a violent, fast-moving fire swept through a Canadian Armed Forces base in Wainwright, Alberta. What followed was one of the worst tragedies for the forces in Canadian soil in peace time,” he said. In a press conference Sunday afternoon, Maj-Gen. L.W. Rutland told reporters that the fire broke out during a training exercise ahead of the soldiers’ deployment to Latvia. The officials at CFB Wainwright were aware of the fire for several hours before it turned toward the training area, Rutland said. Despite the knowledge, the soldiers continued to carry out their exercises. CAF officials believe there was no damage to oil and gas infrastructure as a result of the fire, Rutland said. CFB Wainwright victims identified The following members were killed during the fire at CFB Wainwright, according to Maj-Gen. L.W. Rutland: Nearly 40 patients receiving treatment at regional hospitals The medical response has placed significant demands on hospitals and emergency services in the Edmonton region. Dr. Sayeh Zielke, the CEO of Acute Care Alberta told reporters 19 people are in critical condition, eight are stable, and 12 are ambulatory and are receiving care for injuries that can be assessed without admission. Dr. Steve Fisher, an emergency physician at Edmonton’s Royal Alexandra Hospital, told CTV News Edmonton on Sunday that patients had sustained burns of varying severity, with the most seriously affected being treated at the University of Alberta Hospital, which has a burn intensive care unit. The scale of the response prompted Acute Care Alberta to ask residents to avoid the University of Alberta Hospital emergency department if possible Saturday night, unless they required emergency care. The agency said “significant resources” were needed from Emergency Health Services and Edmonton-area emergency departments into the night. STARS Air Ambulance dispatched two air ambulances from Saskatoon and Edmonton. Helicopters and two aircraft also landed at a nearby medical evacuation site as emergency personnel worked to transport and treat the injured. Soldiers were working with hand grenades: CAF The 3rd Battalion, Princess Patricia’s Canadian Light Infantry and reservists were taking part in high-intensity training ahead of deploymen, Rutland said. The Charlie Company, or C Company soldiers were throwing hand grenades on a hand grenade range and conducting a section attack, with 10 soldiers attacking a simulated enemy when the fire broke out, he added. Code Orange lifted after emergency response Acute Care Alberta also says all Code Orange activations have been lifted following the emergency response to the CFB Wainwright incident, which involved health-care teams and emergency services in Alberta and Saskatchewan. A Code Orange is activated when a mass-casualty event places pressure on the health-care system because of a surge in patients. The code remained in effect for more than 10 hours before being lifted shortly before 1 p.m. Sunday. Investigation underway, terrorism not likely The Canadian Armed Forces will undertake a board of inquiry to examine the events of Oct. 17, Rutland said. A spokesperson for National Defence said Sunday there were no indications the incident was the result of terrorist activity. “As emergency responders continue their work and the situation continues to evolve, the full extent of the impact remains under assessment. Our immediate priority is supporting those affected and notifying next of kin. We will not confirm casualty or injury details until that process is complete,” Laura McIntyre-Grills wrote in a statement to CTV News Edmonton. “While the incident remains under investigation, at this time, there are no indications that it was the result of any terrorist activity.” Retired major-general David Fraser, a CTV military analyst and former commander of NATO forces in southern Afghanistan, described the incident as the worst training tragedy he had witnessed during his military career. “We are now dealing with the worst tragedy that I’ve seen in my entire career,” Fraser told CTV News Channel. Fraser, who was previously posted at Wainwright and trained there extensively, said he had seen no indications the incident was anything other than an accident. He said Canadian military bases have established safety procedures for live-fire and other training exercises. He expects those procedures to remain in place until investigators determine whether changes are needed. Defence Minister David McGuinty was travelling to Edmonton on Sunday to receive a briefing on the latest developments. He said the Department of National Defence was working closely with Alberta’s government and local authorities. High winds contributed to rapidly spreading fire The Municipal District of Wainwright said high winds caused the fire to spread rapidly into the surrounding area Saturday. Officials said the fire crossed the base fence earlier in the day and was being managed south of Wainwright. Crews faced volatile conditions as parts of Alberta experienced wind gusts of up to 100 km/h. Municipal information officers told CTV News Edmonton late Saturday that the spread was under control. Rutland told reporters the wind caused the fire to shift towards the training area, and it crossed fire guards before it was contained. The fire is not believed to be a result of oil and gas infrastructure or outside interference, but the cause is still under investigation. Video captured from private property about one kilometre from Canadian Forces Base Wainwright on Saturday shows flames burning in the area as smoke billows across the sky. The footage offers a glimpse of the fire that prompted a major emergency response at the Alberta military base. Military families urged to seek support The Edmonton Military Family Resource Centre opened Sunday to support military families affected by the incident. Families were invited to connect in a safe and supportive space as they dealt with the aftermath. People needing additional assistance can call the Family Information Line at 1-800-866-4546 for free, confidential support, available 24 hours a day, seven days a week. Officials have said supporting those affected and notifying next of kin remain immediate priorities Canadian Blood Services calls for donations Canadian Blood Services is offering its condolences to those affected by the CFB Wainwright fire and encouraging Canadians to donate blood to help support injured patients. “Our top priority is ensuring patients in Canada receive the blood and blood products they need. We are closely monitoring the needs of patients and hospitals in Alberta and will continue to work with health system partners to ensure those needs are met,” a media spokesperson wrote in a statement to CTV News Edmonton on Sunday. The organization said appointments remained available in Alberta and across Canada, adding that donations in the coming weeks would help maintain the national blood supply. “We are grateful to the many people who have already reached out to ask how they can help. Donating blood is one meaningful way to support patients in Canada, both now and in the weeks ahead. Many appointments are still available throughout Alberta and across Canada, and donations in the coming weeks will help to keep our national inventory strong.” Political and military leaders offer condolences Alberta Premier Danielle Smith described the loss of life and injuries as heartbreaking and said her government was working with federal officials and local authorities. “The loss of life and injuries are heartbreaking. On behalf of the Government of Alberta, I extend my deepest condolences to the families who have lost loved ones and wish those who have been injured a full recovery. Our thoughts are also with the military personnel, families and colleagues facing uncertainty and grief during this incredibly difficult time,” Smith said. Smith said she would travel to Edmonton to meet with provincial ministers and federal officials. The province activated its Emergency Management Cabinet Co-ordination Committee and raised the Provincial Emergency Coordination Centre to Level 3. Ontario Premier Doug Ford also offered assistance with recovery efforts, saying his province stood “ready to help.” “As Canadians, let’s come together to support our brave men and women in uniform, who put their lives on the line to protect our freedoms and our country,” Ford said. Maritime premiers also expressed condolences, noting the close ties between military personnel, their families and communities across Canada. Former Alberta premier Jason Kenney said the tragedy would be deeply felt in the region surrounding the base. “If you live in east central Alberta in the Wainwright area, this base is part of your life, “ Kenney told CTV News Channel on Sunday. “You get to know the soldiers and the base staff (is) a very large part of the whole broader community out in that sparsely populated area.” Kenney said Albertans have a “deep regard for the sacrifices taken by our men and women in uniform.” NATO’s Military Committee also offered condolences to the families of those killed and wished the injured a full recovery. Community and military personnel await further answers The tragedy has affected military families and communities well beyond Wainwright, as personnel from bases across Canada were among those involved. A Barrie-area mayoral candidate, Cathy Keane, said her eldest son was critically injured in the incident. In a social media post Sunday, she said she would travel to Alberta to be with him and her family. “As a mother, right now I need to be with my son and family,” she said. Election day locations in Wainwright to open as planned Elections Alberta says voting locations in Wainwright will be opened as planned on Oct. 19, officials told reporters. Eligible voters in the area will be able to cast their 10 ballots at the Wainwright Communiplex and the Royal Canadian Legion Branch 29 Wainwright. Pro-Canada rally goes ahead in Edmonton A pro-Canada rally was held in Edmonton on Sunday and while attendees were focused on the referendum on Monday, the incident in Wainwright was still top of mind. Organizer Gil McGowan said the Wainwright tragedy “hangs like a real dark cloud” over the event. McGowan, the head of the Alberta Federation of Labour, thanked first responders from around Canada and said it’s a poignant reminder of why Canada is better united. Albertans are set to vote on Monday whether the province should remain in Canada or if a referendum should be held on separation. Smith told reporters the upcoming referendum on Monday will go ahead. With files from The Canadian Press