Pedestrian fatally hit on I-57 on South Side

CHICAGO (WLS) -- A pedestrian was killed after being hit by a truck on the South Side Monday morning, Illinois State Police said.

The incident occurred in the northbound lanes of I-57 near 103rd Street at about 4:53 a.m.. Police had blocked off all but one lane as they investigate, causing a backup several miles long. The lanes were fully reopened at about 7:40 a.m.

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Police said a 25-year-old man from Calumet Park was in a lane of traffic when he was struck and killed. Authorities have not released his identity.

It is not known what led the pedestrian to enter the roadway and an investigation into the incident is underway.