Premise: BOZEMAN, Mont. (AP) — Authorities say four people, including three children, were hospitalized after a gas explosion at a home in West Yellowstone. Shane Grube, chief of the Hebgen Basin Rural Fire District said firefighters were called to the mobile home Tuesday morning. He says the explosion caused a fireball that blew itself out. Two people suffered severe injuries and two were moderately injured. All of the victims were taken to a hospital in Rexburg, Idaho. The fire district is investigating with help from the state fire marshal’s office. No other details were released.
Hypothesis: The mobile home had been rendered immobile.