PORT CLINTON, Ohio (AP) — The body of an Ohio teenager last seen walking to school more three weeks ago was found stuck inside the chimney of a vacant home, and authorities said Tuesday they believe his death was an accident.

It appears that 14-year-old Harley Dilly had climbed an antenna, got onto the roof of the house across the street from where he lived and then went down its chimney, said Port Clinton Police Chief Robert Hickman.

Hickman said there were no signs of foul play. An autopsy was scheduled for Tuesday.

Authorities found Dilly’s body Monday night during another search of the neighborhood, a residential area along Lake Erie that is about 40 miles east of Toledo.

They already had looked around the outside of the house, which had been locked and had no signs of a forced entry, Hickman said.

“We had no reason to believe anyone was in the house,” he added.

Investigators went inside the house and found the boy’s coat and glasses on the second floor next to the chimney. It is unclear why Dilly would have gone into the home.

He was last seen on surveillance video leaving for school on the morning of Dec. 20.

Authorities first thought the teen may have run away from home, because his family had said he would sometimes spend a night away from home if he got upset. At the time of Dilly’s disappearance, Hickman said the teen may have been upset about having electronics taken away from him.

Since then, volunteers and authorities searched through nearby neighborhoods along Lake Erie with help from K-9 teams and helicopters.

Police also had asked residents to review their home security footage, hoping that might offer clues about what happened.