Lanes have now reopened and wreckage has been cleared. Earlier Friday, authorities had shut down the two right outbound lanes just before Thorndale, which caused a massive back-up. The accident also snarled traffic for at least five miles on northbound I-355.
State police responded to the crash shortly after 4:30 a.m., Elgin District trooper Nathan Schramka said. For several hours, a car could be seen in a ditch off to the side of the road.
The location was near northwest suburban Itasca, maps showed.
The crash was fatal, Schramka said, but further details were not immediately available.
The heavy traffic had prompted many drivers to detour onto Old Route 53 as an alternate. Northbound delays were reported there, as well.
(Sun-Times Media Wire contributed to this report - Copyright Chicago Sun-Times 2011.)