The incident happened around 4:30 pm on the 300 block of East Ashmead Street.
When officers arrived, they found the 17-year-old male victim suffering from a gunshot wound in an upper bedroom.
Police say a 9-year-old child shot the teenager.
Investigators first believed the 17-year-old accidentally shot himself.
But they now say that 9-year-old picked up the handgun and pulled the trigger.
No further details have been provided at this time.
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