Published: Aug 22, 2014 12:11 PM EDT

TAMPA, Fla. (AP) - Authorities say the Tampa woman who shot her 7-year-old grandson after mistaking him for an intruder probably won't face charges.
    
Hillsborough County Sheriff's officials told the Tampa Bay Times (http://bit.ly/1BJoz7e ) the Tuesday shooting has been labeled an accident. But an investigation is ongoing.
    
Linda Maddox told deputies she was on high alert because her son was working late and she was alone with her twin grandsons.
    
Officials say the 63-year-old woman placed a chair against the bedroom door where she was sleeping with her grandsons. Around 1 a.m., she heard the chair scraping against the floor, grabbed a pistol and fired once, striking Tyler Maddox in the upper body. He was in critical but stable condition at a hospital.
    
The Department of Children and Families say the children remain in the custody of their father.
    
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Information from: Tampa Bay Times (St. Petersburg, Fla.), http://www.tampabay.com.

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