Inbound train No. 626 left Barrington at 7:27 a.m. and struck a 95-year-old bicyclist at Central and Northwest Highway in Mount Prospect around 7:50 a.m.
The Cook County Medical Examiner's office confirmed an elderly man from Mt. Prospect was struck and killed.
Some trains experienced delays up to two hours after the incident, but trains were on the move again as of about 10 a.m., according to Metra's website.
Metra and Mount Prospect police are investigating. Officials say the man was riding on the sidewalk eastbound on Central when he attempted to cross the tracks with the lights flashing and gates down.
The Sun-Times Media Wire contributed to this report.