Three south suburban police stations are teaming up after a series of attacks on women.
In the latest incident, a woman was sexually assaulted near a Metra train station in Matteson Thursday morning.
Police say the same man might be responsible for six other attacks in Park Forest and Richton Park since March.
The suspect is described as an African-American male around 30-years-old, 180 lbs., short hair with calluses on his hands. He was wearing a black hooded nylon jacket with a white zipper, dark jeans and dark gym shoes.
There is a $500 reward for information leading to an arrest.