Andrew M. Hildebrand, a 30-year-old from Oshkosh, Wisconsin, was last seen on May 12, 2019. He had been interviewed by detectives that day in connection with a sexual assault investigation and was reported missing later that evening, prompting a welfare check. Two days later his silver van was found abandoned at a boat launch near Auburn Lake in Fond du Lac County, a significant distance from his last known Oshkosh location.

An extensive search of the area around the boat launch and Auburn Lake produced no sign of Hildebrand. The Fond du Lac County Sheriff’s Department deployed ground and aerial teams, police dogs, drones, an airplane, a Department of Natural Resources boat, plus submersible robots and sonar to search the lake. Authorities said he was familiar with the Kettle Moraine State Forest area and may have had a .22 rifle when he went missing; they also said he had not threatened the public.

A warrant was issued and on May 20, 2019 a criminal complaint charged Hildebrand with two counts of first-degree child sex assault and with invasion of privacy and attempted invasion of privacy. The case remains unsolved and he has not been seen or heard from since May 12, 2019. Anyone with information that could help locate him is asked to come forward.