It happened around 9:30 p.m. near West 5th Avenue and Sheridan Boulevard.
Officers determined the 12-year-old boy was accidentally shot by a 14-year-old male relative.
Police say the gun belonged to an adult associated with the home where the two boys lived.
The boy was taken to the hospital with non life-threatening injuries.
The 14-year-old is facing charges of theft and minor in possession of a handgun. The case will be presented to the Jefferson County District Attorney's Office next week.
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