The shooting took place around 10:30 p.m. in the inbound ramp of I-55 to DuSable Lake Shore Drive.
Police said a man was shot in the head and transported to Northwestern Memorial Hospital in critical condition and later pronounced dead.
It is unclear what led up to the shooting.
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The ramp was closed as police investigated and has since reopened.
Police also investigated another reported shooting on a Chicago expressway overnight. Troopers responded to reports of a vehicle found with bullets at around 2 a.m. in the outbound lanes of the Dan Ryan Expressway between 87th and 95th streets. No injuries were reported.
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