Police say a young girl has fatally shot herself in Detroit after finding a handgun under her grandmother's pillow.

Detroit police Sgt. Michael Woody says in an email that police responded around midnight Tuesday to a home on the city's northwest side and the girl was taken by medics to a hospital, where she was pronounced dead.

Police say the girl was 4 years old. Broadcasters, citing family members at the scene, report the girl was 5.

According to the initial investigation, police say the girl found the gun in an upstairs bedroom and shot herself while the grandmother was downstairs. Police say two other young children, ages 1 and 3, also were upstairs at the time. They weren't injured.

The shooting is under investigation.