Bonneville County Sheriff's Deputies are investigating the possibility that someone intentionally burned a house down on Brome St.
The fire started in a Bonneville County home around 10 p.m. Monday.
The family living at 4300 E. Brome St. was able to get out of the house alive. One adult did suffer minor burns to the face and had minor smoke inhalation. Three adults, an infant, and a 5-year-old lived at the home.
All three adults were taken in for questioning Monday night. Two were released, but one, a 51-year-old woman, remains on 48-hour psychiatric hold.
"There's a consensus that one of the three adults actually started the fire," said Sgt. Jeff Edwards with the Bonneville County Sheriff's Office.
Idaho Falls Fire Department Division Chief Brad Pettingill said the fact that the fire spread so quickly suggests it might not have been an accident.
"This doesn't appear that it had a lot of time (to burn)," Pettingill said. "To spread through the house so fast is just -- it's not normal."
No one has been charged with a crime, as investigators are still trying to figure out what started the fire.
Damage to the home is estimated at $140,000.