ISP said the deadly crash happened around 8:23 a.m. on westbound I-88 near Oak Brook in DuPage County.
The person struck was a driver who had been involved in another crash and was standing outside of their car near mile marker 138.5. A Jeep hit the pedestrian and fled the scene, police said.
The victim was taken to a local hospital, where they were pronounced dead.
ISP is investigating and did not immediately provide further information.
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