A huge fire swept through a Canadian military base on Saturday, killing at least four people and seriously injuring dozens more.

Prime Minister Mark Carney described it as one of the worst peace time tragedies on Canadian soil in the history of the military.

Here is what we know about the deadly incident so far.

Few details about what triggered the deadly fire at Canadian Forces Base Wainwright, which broke out at around 16:00 local time (22:00 GMT), have been confirmed by authorities so far.

Local media reported it may have been started when a gas main was struck during a live firing exercise taking place on the grounds.

Carney said a “violent, fast-moving fire swept through the base” without confirming what started it.

The Municipal District of Wainwright posted on social media that the fire had “spread rapidly due to high winds”.

The prime minister said military and civilian fire crews “fought this fire throughout the night in some of the worst conditions imaginable, risking their lives to protect their fellow Canadians”.

The Canadian defence ministry has said the cause remains under investigation, and “at this time, there are no indications that it was the result of any terrorist activity”.

It has not been confirmed if those injured were on the base’s sprawling ranges where exercises are carried out, or whether the fire spread to living quarters.

Four service members are confirmed to have died, Carney said on Sunday.

He also said “dozens” had been “seriously wounded”, without providing further information on their conditions.

Prior to Carney addressing the nation, Canadian media reported the death toll as seven citing unnamed military sources.

The prime minister did not indicate whether or not the government expects the death toll to rise.

The names of those who lost their lives have not been identified but their families have been informed.

On Saturday evening, Royal Alexandra Hospital in Edmonton declared a code orange – a disaster response protocol for a high-casualty incident. It was stood down on Sunday afternoon.

Alberta’s health service said the emergency response lasted for 10 hours, and involved 22 ambulances and eight aircraft.

Ongoing care for the injured is expected to be “intensive”, a statement continued.

A stream of ambulances were seen arriving at the hospital and one doctor told Canadian public broadcaster CBC that the facility had been “completely overwhelmed” by the number of patients.

Canadian Forces Base Wainwright is located in a rural area of the western province of Alberta – around 120 miles (193km) from Edmonton and 180 miles (290km) from Calgary, the province’s two largest cities.

It is one of Canadian Army’s busiest military training bases and its airfield is also used by the Royal Canadian Air Force.

It population fluctuates but more than 1,000 people can be based there at any given time.