CHATTAROY, Wash. -

A criminal investigation has been launched into a possible explosion and fire at a home in Chattaroy that left two people critically injured.

Investigators believe an explosion and the resulting fire was an attack perpetrated by a man against his estranged wife.

Twenty four hours after the fire, Major Crime detectives are still at the scene sifting through evidence at the remains of the mobile home, located in the 3200 block of E. Chattaroy Road, where the fire happened. They are investigating the case as a domestic violence assault.

Neighbors said Wednesday night the fire began with an explosion. Spokane County Sheriff's deputies and Spokane County Fire District #4 responded and battled the fire.

When authorities arrived the man and woman who were inside the house when it caught fire were outside and badly burned. Deputies say the man may have released propane gas and then ignited it when the two were inside.

The couple was flown to Spokane and then transferred to Harborview Medical Center in Seattle.

"Terrible, absolutely terrible, a million phone calls, I went out there this morning. I had to see it. I just talked to a nurse at Harborview and asked her, 'Is my daughter still alive?' and she said 'Teah she's still alive we've been very busy with her this morning they were doing skin grafts,'" the victim's mother, Marietta Parvey said.

Both the man and woman, who were married but had been separated for several months, are in critical condition at Harborview.