The woman told police she was in the parking lot of Golf Mill Shopping Center, walking to her car with a friend, around 4:50 p.m. on March 9 when she saw a man slowly driving next to her, according to a Niles police report.
The woman said she looked at the man and saw "his pants down" and him touching himself, the report states.
The woman told police she saw the man park his vehicle at different spots in the parking lot, the report states.
At one point, she approached his vehicle to take down his license plate number, the report states, at which time she saw him continuing to touch himself with his pants down inside the vehicle.
The woman called her husband, the report states, and both Niles police and a sheriff's police officer responded to the scene.
Working with the license plate number, authorities found the man a short time later in the parking lot near his residence in the 9600 block of North Dee Road in Des Plaines, according to the report.
The Des Plaines man, identified in the report as William F. McDonald, was arrested and charged with public indecency. He was released on bond and is expected to appear in court again on March 28 in Skokie.
McDonald could not be reached for comment.