Police said the shooting happened in the 1100-block of South Wabash Avenue just before 6:30 p.m.
A 23-year-old man was riding a bike when he got into an argument with another person, identified only as male.
The argument became physical, and that's when the offender took out a gun and fired a shot at the bicyclist, police said.
The victim, shot in the lower back, was transported to Northwestern Hospital in fair condition.
The suspected shooter fled the scene eastbound on Roosevelt Road on a blue bicycle.
There is no one in custody. Area Three detectives are investigating.
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