Via CBS Chicago:
Police are investigating the possibility that somebody hijacked a CTA train and sent it crashing into another train, CBS 2 is reporting.
At least seven people were hurt when the trains collided in West Suburban Forest park, according to the CTA.
Forest Park Mayor Anthony Calderone said 48 people were transported to 10 area hospitals. The injuries are considered mostly minor, including shoulder and back injuries.
A westbound train was standing on the tracks near Harlem around 8 a.m. when a train traveling eastbound on the same track smashed into it, the CTA said.
UPDATE: 12:41pm EST
ABC News reports that police are stating the empty train may have been deliberately set in motion to cause an accident.