TURLOCK (CBS13) — A make-believe game between a pair of young siblings took a scary turn inside their Turlock home.

Turlock police say a 10-year-old girl accidentally shot her 12-year-old brother with a loaded gun found inside their home that was not locked up.

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A family-member tells CBS13 the boy found his uncle’s loaded handgun inside a closet and the two started playing with it while their mother was sleeping inside the home and their uncle was in another part of the house.

The Turlock Journal reports the two were playing a game of cops and robbers when the gun went off.

Family says the bullet hit the boy in the hand and fragments also hit him in the head. The injury was so severe he was life-flighted to a local hospital.

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Turlock Police Chief Nino Amirfar says he was on duty Friday when the call of a child shot came across the radio. He describes the call as one of the most difficult to which a law enforcement officer responds.

“It was a gut-wrenching call,” Chief Amirfar said. “I just ask everyone that’s a gun owner please make sure you secure your weapons.”

California law requires loaded firearms in homes with children to be stored in a locked container, or the firearm itself have a locking device on it. Turlock Police are preparing to recommend a charge of unlawful storage of a firearm in this case.

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The 12-year-old boy is listed as in critical but stable condition. His family says he will need to undergo surgery before he is released from the hospital.