9:19 AM UPDATE
All lanes of traffic on NB I-55 and on Frontage Road remain closed at this time. The vehicles that were stuck following the accident have been moved through.
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At 4:23 AM this morning, a vehicle traveling westbound on Frontage Road at a high rate of speed hit the curve and went airborne through the barrier onto northbound I-55 where it was struck by another vehicle. The driver of the speeding vehicle has perished. The driver of the vehicle on I-55 sustained non-life threatening injuries.
I-55 and Frontage Road are both shutdown for investigation and cleanup and are anticipated to remain closed for several hours. Please find alternate routes. Romeoville Police are working to mitigate traffic for those stuck on northbound I-55 and surrounding roads.