Published: Aug 19, 2014 12:58 PM EDT

TAMPA, Fla. (AP) - A grandmother shot and critically wounded her 7-year-old grandson early Tuesday after mistaking him for an intruder who had broken into her home, the Hillsborough County Sheriff's Office said.
    
Linda Maddox, 63, and her twin grandsons were sleeping in a bedroom at about 1 a.m. after her son, who is the boy's father, had left for work at the postal service, police said. Maddox told deputies she had placed a chair against the bedroom door handle for extra protection while they slept.
    
When she heard the chair sliding against the wood floor, she assumed it was an intruder and grabbed a loaded .22-caliber revolver she keeps by the bed and fired one shot in the dark toward the door.
    
Deputies say seconds later she heard her grandson Tyler Maddox scream. He was shot once in the upper body. He was taken to a hospital, where he was listed in critical condition.
    
Neighbor Jonathan Aristizabal, 18, said he has lived in the middle-class community for six months and hasn't noticed anything that would make him think the area is unsafe. He said he often saw the kids playing in the front yard.
    
"It's a big tragedy," he said. "They're a really good family."

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