The luggage was found on the platform level shortly before 10 a.m. at the station at 500 W. Madison, according to Metra spokesman Tom Miller. Union Pacific trains were not being allowed to enter or depart the station as of 11 a.m.
Police officers and Bomb Unit members were called to the station to assist Metra police with the investigation, according to Chicago Police.
Parts of the station were evacuated, according to Miller.
Chicago Fire Department spokesman Larry Merritt said CFD crews were called to the station for a hazardous materials response.
This is a developing story. Listen for updates on WLS-AM and wlsam.com.