The boy was inside a home in the 3100-block of West Flournoy Street in the city's Lawndale neighborhood about 4:25 a.m. with another boy when they found a gun, police said.
The gun went off once, shooting the boy in the chest, CPD said.
Police took the boy to Mt. Sinai Hospital, where he later died.
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No other injuries were reported.
The weapon was recovered on the scene.
Area Four detectives are investigating.
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