Police said the crash happened in the Calumet Heights neighborhood's 2800-block of East 95th Street just before 3:45 p.m.
A man was standing near the street when a sedan, traveling eastbound on 95th Street, struck him and continued driving, police said.
Witnesses told ABC7 that the driver appeared to be going at a high rate of speed and started to drive the wrong way in the westbound lanes to get around the traffic before hitting the victim.
One witness said the victim had just purchased food from a nearby gas station and was walking across the street, back to a truck, the driver hit him.
Another witness, who did not want to peak on camera, said after the victim was hit, he had trouble breathing.
That witness said one woman then got out of her car and started to perform CPR on the man before help arrived.
Police said the victim was ultimately transported to the University of Chicago Medical Center in critical condition.
Police are trying to track down the driver. No one is in custody and area detectives are investigating.
Authorities did not immediately provide further information about the crash.
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