A Chicago Transit Authority Blue Line train derailed around 2:50 a.m. Monday, a traditionally quiet time at the airport.
Authorities say none of the injuries are life-threatening. Chicago Fire Commissioner Jose Santiago told news crews most were able to walk away from the wreck unaided.
Investigators from the NTSB are expected to arrive Monday afternoon to assist in the investigation.
Copyright 2016 Nexstar Broadcasting, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.