LA PORTE CITY, Iowa — Authorities in northeastern Iowa have confirmed the human remains found in a creek earlier this month are those of an autistic teen who vanished from his small hometown in April.

La Porte City Police Chief Chris Brecher said Wednesday afternoon that the remains are those of Jake Wilson, who was last seen April 7 when he went for a walk blocks from his home along Wolf Creek.

Brecher says Wilson's cause of death has not been determined. The remains were discovered Aug. 14 in the creek by kayakers.

Wilson's disappearance led to a massive search involving the FBI, state and local police officers, and hundreds of volunteers in the town of about 2,300.

Wilson's family said he didn't have his glasses when he went for the walk. Wilson was 16, but his family has said that he had the mental capacity of a 9-year-old boy.