The Washtenaw County Sheriff’s Office released a sketch Saturday morning of a man suspected of assaulting a security guard at the Maplewood Apartment Complex in Ypsilanti Township.

The man in the sketch was described as black, between 5 feet 8 inches and 6 feet tall, heavily built and 20 to 30 years old.

The security guard was on foot patrol at the complex across the street from St. Joseph Mercy Hospital when three men jumped her from behind and began to assault her at about 11:40 p.m. Tuesday, the police said.

She told police she was only able to get a good enough look at one of the men to describe him for a sketch. It was unclear whether they used a weapon, but the security guard was unarmed and fought back before the men fled the scene.

The security guard told police the attackers may have been driving a pick-up truck with a cap covering the bed, but she could not describe the color.

The woman was taken to St. Joseph Mercy Hospital and treated for serious, but not life-threatening injuries, the police said.

Anyone with information on this attack can call Detective Sinks at 734-973-4874, the Washtenaw County Sheriff’s confidential tip like at 734-973-7711 or the Crime Stoppers anonymous tip line at 1-800-2587.