An 11-year old Kalispell boy accused of fatally shooting his father with a shotgun has been charged with mitigated deliberate homicide.

Police say 47-year-old Patrick Gretsch died Monday evening after he was shot in the chest with a 20-gauge shotgun. Officers arrived at a Kalispell trailer park for what was initially reported as an accidental shooting.

Police Chief Roger Nasset said earlier this week that several people were in the trailer at the time of the shooting, and there had been an argument between Gretsch and an adult family member. The chief said that during the disturbance, the boy fired two shots, one through the ceiling and the other into his father's chest.

Court records state that the boy's mother said he shot his father to protect her.

Flathead County Attorney Ed Corrigan says the boy, whose name has not been released, is the youngest person he has ever prosecuted on the charge.