TAMPA, Fla. -

A 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 said Tuesday's shooting has been labeled an accident, although 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.

The 63-year-old woman placed a chair against the bedroom door where she was sleeping with her grandsons. She heard the chair scraping against the floor early Tuesday morning, grabbed a pistol and fired once, striking Tyler Maddox.

Tyler Maddox was in critical but stable condition at a hospital.

The Department of Children and Families said the children remain in the custody of their father.

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