FAIRFAX CITY, Va. (AP) — A homeless man has been arrested after police discovered a 15-foot-deep tunnel they say he has been living in.

Fairfax City police spokeswoman Sgt. Natalie Hinesley says 25-year-old Yosue Joel Rios was arrested Sunday on a charge of property destruction after digging the tunnel in Van Dyck Park.

Hinesley says Rios made the tunnel his home and camouflaged it by covering it with a large piece of plywood. She says officers discovered a pillow, hand-held gardening tools and other personal items inside.

Hinesley says employees from the city’s Department of Public Works filled in the tunnel Monday morning.

She told NBC Washington that “I haven’t seen anything like it. … He was studying several topics,” including the English language.

Rios, who was wanted for failure to appear on a traffic charge in Arlington County, was held without bond. It isn’t clear whether he has an attorney.

WTOP contributed to this report.