The shooting took place at about 8:40 p.m. in the 2300-block of West Devon Avenue.
Police said a man was inside a car when he got into a fight with a pedestrian.
The man got out of the car and the pedestrian took out a gun and shot him in the abdomen, police said.
The victim was transported to St. Francis Hospital in serious condition, police said.
The suspect fled the scene and is not in custody, police said. Area Three detectives are investigating.
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