The San Diego County Sheriff's Department is investigating a report of a shooting by a 3-year-old that left the child's 1-year-old sibling dead.
The shooting was reported around 7:30 a.m. Monday at a home in the 1100 block of South Stagecoach Lane in Fallbrook, a community 20 miles northeast of Oceanside.
A caller told sheriff's dispatchers that the 3-year-old had accidentally shot the baby, the department said in a news release.
San Diego sheriff's deputies went to the home and confirmed that the older child had gotten hold of a gun that had not been securely stored in the home, the department said.
The 1-year-old girl was found with a head injury and taken to Palomar Hospital, where she was pronounced dead.
"The Sheriff's Department extends our sympathies to the family and those affected by this death," the department said.
The shooting remains under investigation by San Diego County sheriff's homicide detectives. The department said there were no outstanding suspects.
The San Diego County district attorney's office has been notified, the department said.