An explosion sent a civilian to hospital with life-threatening injuries and two officers to hospital with severe burns following a standoff at a home northeast of Cornwall, Ont. Monday morning.

Ontario Provincial Police say the explosion happened after officers responded to a 911 call to deal with a suicidal 27-year-old male who was allegedly threatening to burn down a house on Beaverbrook Road near Martintown.

Police say the residents of the home left and called police when the man showed up.

When police entered the home to deal with the suspect, an explosion ensued, engulfing the house in flames while the man and two officers were inside.

The officers received severe burns and were immediately transported to Cornwall hospital. One of the officers has since been transferred to the Ottawa Hospital's General campus.

The male suspect received life-threatening injuries in the explosion and was flown to the Ottawa General Hospital.

Two other police officers were also treated in hospital for smoke inhalation.

"The citizens of Ontario should have a great sense of pride in regards to the actions of these very brave officers," said Commissioner Julian Fantino in a news release issued Monday. "We are very grateful for their dedication to the citizens of this province."

The Special Investigation Unit, which investigates whenever police are involved in serious injuries or deaths, is probing the incident.