While the timing was bad, the impact for the moment appeared to not be too severe.
An Amtrak spokesperson said around mid-afternoon, a locomotive became disabled as it pulled into Union Station. That caused a backup on the track, and for a time trains were not moving in or out of the station.
Officials said at least two Metra Southwest Line trains were impacted and at least one canceled. Some other lines, including BNSF and Heritage Corridor, were seeing 30 minute delays.
Officials said they are working to reroute the backed up trains into the station, and shortly before 4 p.m. Metra trains began coming in and out, serving passengers.
Officials said they are waiting until after the evening rush to remove the disabled train.
Earlier this week switching problems at Union station caused significant delays during the evening commute, but that issue appears to be unrelated to Friday afternoon's events.