Michael Gillis is a spokesman for Metra, the suburban Chicago commuter rail service.
Gillis says six passengers were taken to a hospital with minor injuries Monday after the Rock Island District line train from Joliet hit the "bumping post" at the end of the LaSalle Street platform.
The accident happened around 8:45 a.m. A less serious incident occurred at the same station around 6:15 a.m., but no passengers were injured.
Gillis says the agency is investigating what caused the incidents; authorities have indicated they were weather-related.
All Metra trains are being told to enter downtown stations at "walking speed."