Authorities say Michael Black, 43, and Sherilyn Williams, 51, were traveling southbound in the far right lane of I-294 in a black Nissan Murano when they were struck by an unknown vehicle. The impact forced the Murano into the center median wall.
The unknown vehicle left the scene of the crash.
They were transported to the hospital, where Black was pronounced dead. Police say Black was not wearing a seatbelt at the time of the crash.
Williams suffered non-life-threatening injuries.
Illinois State Police are investigating.