Police said the shooting happened in the East Side neighborhood's 9900-block of South Ewing Avenue just before 5:45 p.m.
A male suspect of an unknown age approached the men, took out a gun, and fired shots, police said.
All three victims were shot in the abdomen, police said.
A 52-year-old man was transported to the University of Chicago Medical Center in critical condition.
Another man, 48, was taken to the same hospital in good condition.
A 41-year-old man was transported to Christ Hospital in good condition.
Area Two detectives are investigating. Authorities did not immediately provide further information about the shooting.
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