AlQa'dah 25, 1434, Oct 1, 2013, SPA -- A Chicago Transit Authority (CTA) train collided with a standing train at a station in a western suburb during the Monday morning rush-hour, leaving at least 33 people injured, a CTA official said. The collision happened at a ground-level station in Forest Park, west of the city, CTA spokeswoman Catherine Hosinski said. Thirty-three people were transported to nine area hospitals with what appeared to be non-serious injuries, she said. Forest Park Mayor Anthony Calderone gave a higher number of injured, saying 48 people had been transferred to 10 area hospitals. The National Transportation Safety Board said it was sending investigators to Chicago to probe the collision. The CTA also is investigating to determine whether there was an operator or anyone else on the colliding train, which had no passengers or crew. Service had resumed across the affected line by midday, but trains are not stopping at the station where the collision occurred, the CTA said.