The woman, 47, was attacked by a man around 5 a.m. Wednesday on the train platform at the Chicago stop, 800 N. Milwaukee Avenue. Officials say the man approached the worker after she had crossed the platform to use the bathroom. He fled when he heard other people, officials said.
Police say the suspect is a 20-32 year old black man who wears his hair in afro. He's 5'8" to 5'11" and weighs between 170 and 200 pounds. He was wearing a white tank top and blue jeans.
The woman declined medical treatment at the scene. Police are investigating.