ISP said the shooting happened in the inbound lanes of Interstate 55 between California and Western avenues around 6:45 p.m. That's in the city's Brighton Park neighborhood.
The victim was transported to a local hospital with non-life-threatening injuries, ISP said. What led up to the shooting was not immediately clear.
Troopers temporarily shut down the inbound side of the expressway to look for evidence.
ISP did not immediately provide further information about the shooting.
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