CHICAGO (CBS) — A 26-year-old autistic man is missing from his home near Sherman Park for seven months.

Zerrell Washington left his home in the 5600 block of South Laflin Street for a doctor’s appointment, and ran off in the direction of Garfield Boulevard, police said.

Washington is described as an African-American male, standing 5 feet 8 inches tall and weighing 180 pounds, with black hair, brown eyes and a medium complexion.

He was last seen wearing a gray shirt, black jeans, and black and white gym shoes on with his mother’s phone number printed on them. He also carries a small white cooler.

Washington likes riding buses and ‘L’ trains, police said.

Police said Washington has autism, but have not indicated how severely he is affected on the autistic spectrum.

Anyone who sees Washington is asked to call 911, or the police Wentworth Area Special Victims Unit, at (312) 747-8385.