HILLSIDE, Ill. (WLS) -- Illinois State Police are investigating after a body was found on the Eisenhower Expressway Monday afternoon.Police tell ABC7 Eyewitness News that the body found between concrete walls on the inbound Eisenhower near Wolf Road in suburban Hillside appears to be that of a pedestrian who was hit by a passing car early Monday morning, possibly while trying to cross the highway.The victim has been identified by the Medical Examiner as 22-year-old LaShawn Williams.It is unclear whether Williams was walking for help, perhaps after encountering car trouble. The section of the highway is elevated with no immediate access to surrounding neighborhoods.All lanes of I-290 eastbound at Wolf Road have reopened to traffic.Commuters experienced a three-mile backup Monday evening, as traffic on the inbound Eisenhower extension was rerouted for the investigation. Traffic heading inbound from I-88 is not impacted, other than a large gaper's delay.The identity of body has yet to be revealed.