The shooting happened just after 2 p.m. Monday on the 3900 block of West Cermak Road.
Police said the victim was sitting in a car when the suspect ran up and started shooting, striking him in the head and body.
The 37-year-old victim was transported to Mount Sinai Hospital in critical condition.
No one is in custody and Area Four detectives are investigating. Police did not immediately provide further information about the shooting.
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