The Pierce County Sheriff's Department said an 11-year-old boy accidentally fired a handgun and struck his 9-year-old brother in the leg at their home in Spring Valley.
The incident happened Saturday afternoon. The Sheriff's Department said the 11-year-old was unloading the gun when he accidentally fired it.
The 9-year-old was taken to a hospital in Menomonie before being airlifted to Regions Hospital in St. Paul.
The Sheriff's Department is investigating the shooting but has not released the victim's name.
A Regions media representative said Sunday that the hospital cannot release his condition without being provided his name.