Authorities say that an 11-year-old boy shot a teen who was trying to break into his St. Louis home yesterday afternoon.

Police say the 11-year-old boy was home alone with his 4-year-old sister when two teens tried to break into their home twice before one of the suspects got into the home through an unlocked front door.

That's when cops say the 11-year-old boy opened fire, killing the 16-year-old suspect. His body was found in the foyer with a gunshot wound to the head.

The second suspect fled, but has since been taken into custody. Authorities have not released his identity.

The 11-year-old boy’s mother says she bought the gun because of previous break-in attempts, but authorities want to know why the children were home alone with easy access to the firearm.

No one has been charged yet in connection with the shooting.

The children in the home were not injured.

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