Details scarce in daylong death investigation that closed I-290

Authorities have not released very many details into a death investigation that closed both directions of Interstate 290 for more than seven hours Thursday.

Federal officials said Friday afternoon was that it was due to an explosion, and that “no evidence was found to indicate this was connected to any other event or that any other individuals were involved,” according to a statement posted on X Friday afternoon by the FBI and the Bureau of Alcohol, Tobacco, Firearms and Explosives.

Illinois State Police officials said they were “supporting an active federal investigation into the incident.”

The Cook County medical examiner’s office scheduled an autopsy Friday for an unidentified individual who was pronounced dead at about 1:45 p.m. in the westbound lanes of I-290, just west of 25th Avenue in Hillside. The medical examiner’s website says the person was a white man.

Due to the investigation, Mannheim Road to I-290 was closed. Mannheim Road over I-290 also was closed. Interstate 88 eastbound to I-290 eastbound was closed as well, state police said. Traffic on I-294 near the area also was affected.

The closures began around 11 a.m. and roads were reopened just before 7 p.m.

Drivers were diverted, causing extensive delays throughout the day.

No other injuries were reported.