Kyle was last seen on August 17, 2001 in Boise County, Idaho. He was camping in the Pine Flats area with his brother and a friend at the time. They had used substances that night, and the next day the police arrested Kyle's brother, his friend, and one of the men's wives, all of whom were still under the influence and hallucinating. The woman told police Kyle had run away from the campsite in the middle of the night, saying he was going to find a McDonald's restaurant. He left his wallet and $300 in cash behind. He never returned and has never been heard from again. Investigators initially assumed he'd hitchhiked out of the area. Authorities conducted a search in the Pine Flats area in 2013, looking for Kyle's remains, but found nothing of interest. His disappearance remains unsolved.