TAMPA, Fla. Sheriff's deputies in Florida say a 7-year-old boy is in critical condition after his grandmother mistook him for an intruder and shot him.

The shooting happened around 1 a.m. Tuesday in Tampa.

According to Hillsborough County Sheriff's officials, 63-year-old Linda Maddox and her twin grandsons were sleeping after their father had left for work.

Maddox told deputies she had placed a chair against the bedroom door handle for extra protection. When she heard the chair sliding against the floor, she assumed it was an intruder and grabbed a loaded .22-calibre revolver she keeps by the bed and fired one shot in the dark toward the door.

Deputies say seconds later she heard the screams of her grandson Tyler Maddox. He was shot once in the upper body. He was taken to a hospital.