New tragedy in Texas linked to the proliferation of firearms in the USA: a three-year-old girl found a loaded semi-automatic pistol at home and accidentally shot her 4-year-old sister, killing her.
The two girls had been left alone in the room, while five adults, all family members or friends, were in other areas of the house.
Harris County Sheriff Ed Gonzales said.
The investigations will ascertain any responsibility of adults for leaving the weapon loaded and unattended in an unsafe place.