Chicago Police say the woman was standing on the platform just south of downtown just before 6 a.m. on Friday when she apparently suffered a medical emergency and fell onto the Red Line tracks, reported the Associated Press.
Police said the woman was found on the tracks in a restricted area, according to WGN. She showed signs of electrocution and was pronounced dead at the scene.
Police say two Chicago Transit Authority workers were also taken to a nearby hospital after suffering panic attacks.
The incident is being investigated as a crime as of Friday morning, according to the Chicago Fire Department.