Police say on Feb. 27, shortly before noon, a man using a wheelchair asked a TTC employee to assist him to the upper level of Union. While in the elevator, the 34-year-old woman was allegedly sexually assaulted, police say.
The suspect is described as white, 35 to 45 years old, 250 pounds with brown hair and two large moles on his right cheek.
At the time, he wore a blue windbreaker jacket, a blue tuque and one black Croc.
Police have released security camera images of the suspect.