The Denver Post reports authorities were called to the home at about 9:30 p.m. Friday and found the victim with non-life-threatening injuries. The older boy is being held for investigation of theft and possession of a gun by a minor.
Police Detective Ryan Mckone says the boys found a handgun in the home, and the older boy accidentally fired a shot while the two were playing with the weapon. Mckone added that it appears adults were in the home at the time.
The victim was taken to a hospital in stable condition.
Police did not say how the two boys were related.
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