Mark O'Neill, a 45-year-old man from Harbor Beach, Michigan, went missing on October 16, 1988. His disappearance has remained a mystery, with very few details available regarding the circumstances leading up to it. Mark was last seen in the Harbor Beach area, and his case has been classified as a missing person investigation. There has been little to no physical evidence to explain what may have happened to him, and despite efforts from law enforcement, no major leads have emerged in the
years since.
At the time of his disappearance, Mark's case was logged in the National Missing and Unidentified Persons System (NamUs), where authorities continue to seek information. Investigators urge anyone with knowledge of Mark's whereabouts or any details related to his case to come forward.Last Seen: Oct 16, 1988
