Police said troopers responded at about 3:27 a.m.to the Paulina Street ramp to I-290.
One person was transported to a hospital, where the person was pronounced dead.
Police have closed the entrance ramp as they investigate.
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Further details were not immediately available.
Anyone with information is asked to contact ISP at 847-294-4400, or email ISP.CrimeTips@Illinois.gov. Witnesses can remain anonymous.