HOUSTON (CBSDFW.COM/AP) – Harris County prosecutors say a grand jury has indicted a Texas sheriff’s sergeant after his young stepson shot and injured himself last year with a weapon the deputy had left in an unlocked gun safe.

Authorities announced Thursday, Harris County Sheriff’s Office Sgt. Tommy Anderson faces a charge of making a firearm accessible to a child.

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Harris County District Attorney Kim Ogg says Anderson, 49,  was on a walk with his daughter in July 2018 when his then 4-year-old stepson found his handgun at their home in Hockley, located northwest of Houston, and accidentally shot himself in the head.

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4-year-old shoots self in head in Hockley, Texas in July 2018. (courtesy: KTRK-TV)

Prosecutors say the gun wasn’t Anderson’s service weapon.

The misdemeanor charge carries a sentence of up to one year in jail.

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(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)