The shooting happened at about 9:14 p.m. near the CTA Racine Station on the Near West Side, police said.
CPD officers responded to a call and found a person shot in the upper right thigh.
Police confirmed the shooting happened inside the CTA train car.
The victim was taken to an area hospital and is expected to be OK.
No other injuries were reported.
Police did not provide any further information about the victim.
Nobody is in custody.
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