About 5 a.m., the woman and the attacker were the only passengers on a Red Line train while it was traveling southbound between the Fullerton and North/Clybourn stations, according to a community alert from Chicago Police.

The woman declined medical attention, police said.

The assailant was described as a black man between 35 and 45 years old, standing between 5-foot-6 and 5-foot-8 and weighing between 130 and 150 pounds. He had short black and gray hair with a short but full beard, and was wearing a long tan jacket, police said. He also had long fingernails and crooked teeth, police said.

Surveillance footage of a man suspected of attempting to sexually assault a woman on a North Side Red Line train early Sunday | Chicago Police
Surveillance footage of a man suspected of attempting to sexually assault a woman on a North Side Red Line train early Sunday | Chicago Police

A suspect is in custody and and charges are pending against him Monday morning, police said.