Boy who shot girl over puppy got gun from unlocked closet, police say

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New details are emerging on how an 11-year-old Tennessee boy obtained a shotgun that fatally wounded an 8-year-old girl.

According to Jefferson County Sheriff Bud McCoig, the boy used his father's 12-gauge shotgun which was in an unlocked closet.

Neighbors said the two had been arguing over a puppy, WBIR reported. Chasity Arwood told WBIR that the boy was "wanting to see a puppy. The little girl laughed and told him no. That was it."

MaKayla "BooBah" Dyer, 8, died when the boy shot her in the chest on Saturday.

The two children went to the same school.

The boy faces first-degree murder charges. The Jefferson County DA will determine if the boy will be tried as an adult.