MINNEAPOLIS (WCCO) — A Minneapolis father whose 4-year-old son found a gun in the home and accidentally shot and killed his 2-year-old brother with it has been found guilty on four criminal counts, including two counts each of manslaughter and child endangerment.

Before last December’s incident, 31-year-old Kao Xiong left one of his semi-automatic hand guns under his pillow, which is where the 4-year-old found it. Xiong and his wife were apparently making lunch in the lower level of the house when the accidental shooting happened.

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Prosecutors said that the pistol was used in the shooting lacked a working safety and was one of several weapons police found improperly stored in the home.

On Friday, a jury acquitted Xiong of one count of gross misdemeanor child endangerment.

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Hennepin County Attorney Mike Freeman called it a “tragic case” and recognized the struggle to balance the family’s grief over the loss of the young child and the violation of the law that resulted in his death.

There was an effort on both sides to work out a plea bargain, but they weren’t able to reach one.

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Aside from the gun that killed the child, investigators found three handguns, three bolt-action rifles and a semi-automatic rifle in the home. Xiong told police he is an avid hunter.