A 3-year-old girl died Tuesday after being shot by her 7-year-old brother in their Westminster home.

The incident happened at about 10:20 a.m. in a residence on Moore Circle near 107th Avenue, according to a police department news release.

Two younger siblings were playing with the 7-year-old when he found an unsecured and loaded shotgun in the home, police said.

“While playing, the older brother tragically shot his 3-year old sister,” the release said.

The girl was taken by emergency responders to a trauma center but her injuries were fatal, police said.

Michaela Dawn Harman, 24, the children’s mother, and a single parent, was home at the time of the incident, police said. Harman is the owner of the weapon and she has been arrested on suspicion of child abuse resulting in death, police said. The children are temporarily in the care of Jefferson County Human Services.

Guns, as part of a safety precaution, should be stored unloaded and securely, separate of ammunition, police said. Gun owners should utilize child-proof devices.