Police said the shooting happened in the South Shore neighborhood's 2700-block of East 75th Street around 9:40 a.m.
A 28-year-old man was arguing with someone, who took out a gun and shot him, police said.
The victim, shot in the chest, was transported to the University of Chicago Medical Center, where he was pronounced dead.
The shooter fled the scene.
Area One detectives are investigating.
Authorities did not immediately provide further information.
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