A one-year-old girl has died in California after receiving a accidental shooting by his brotheronly two years older than her.

The events occurred around 7:30 am local time (13:00 GMT). Local police received a call to report gunshots at a home in Fallbrook, a northern suburb of San Diego, the San Diego County Sheriff’s Office has reported.

When the police officers arrived at the scene, they learned that the shots had been fired by a three-year-old boy who managed to gain access to a gun that had no safety and “accidentally” shot her younger sister in the head.

Police have not released the name of the deceased minor “out of respect for the family and for being a minor,” the sheriff’s office said in a statement.

The authorities have opened a investigation to clarify “with more details” the cause of death. California is one of the states with the greatest restrictions on carrying weapons, allowed for those over 21 years of age.