According to the Metra website, inbound and outbound trains are on the move and approaching the Naperville area slowly as of 8 p.m. Friday.
BNSF train No. 1279 struck a pedestrian at Columbia Avenue in Naperville about 6:30 p.m., Metra spokesman Michael Gillis said.
The train left Union Station and 5:49 p.m. and struck the pedestrian just east of the Naperville station, where the train was not scheduled to stop, Gillis said.
Information about the person struck was not immediately available.
The train was scheduled to arrive in Aurora at 6:40 p.m., but remained stopped at 8 p.m. for a police investigation, Gillis said.
At least eight other BNSF trains have been delayed up to 95 minutes because they cannot pass during the police investigation.
The Sun-Times Media Wire contributed to this report.