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Mark ONeill Missing Person Case

Last seen in Harbor Beach, Michigan on Oct 16, 1988

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Victim Details

Mar 25, 2011

Jul 9, 2019

Mark

ONeill

83

45

68 inches

180 lbs

White / Caucasian

Male

Oct 16, 1988

Harbor Beach

Michigan

Huron County

48441

9831

Huron County Sheriff's Office

Bad Axe

Michigan

Huron County

48413

Daryl Ford

Detective

250 East Huron Avenue, Michigan

9892696500

County

Law Enforcement

4415-88

Oct 17, 1988

Huron County Sheriff's Office

Brown

Brown

Brown

Oct 2, 2026


Area Last Seen:

Case Description

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Summary based on the NamUs case record (MP9862) and 1 other source
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

Links to Additional Sources (1)

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  • Missing Person / NamUs

    • Possible Unidentified Matches (4)

    Unidentified remains cases whose details are consistent with this person, ranked by how closely they compare. Fields that are unknown in either case are left out of the score.

    80%Moderate
    John Doe — Detroit, Michigan - unidentified case UP8237
    John Doe — Detroit, Michigan
    UP8237 • Found Jun 11, 1994
    View case
    Sex ✓Male
    Age 100%Est. 35–45 vs 45 when missing
    Race 100%White
    Location 74%106 mi away, same state
    TimingFound 6 years after last seen
    Height 100%5'8" vs 5'8"
    Weight 77%141 lb vs 180 lb
    Hair 100%Brown vs Brown
    Eyes 100%Brown vs Brown
    76%Possible
    John Doe — Chicago, Illinois
    UP128949 • Found Aug 23, 1992
    View case
    Sex ✓Male
    Age 100%Est. 40–50 vs 45 when missing
    Race 100%White
    Location 46%288 mi away
    TimingFound 4 years after last seen
    Height 100%5'9" vs 5'8"
    Weight 100%174 lb vs 180 lb
    Hair 100%Brown vs Brown
    Eyes 100%Brown vs Brown
    75%Possible
    John Doe — Ecorse, Michigan - unidentified case UP85671
    John Doe — Ecorse, Michigan
    UP85671 • Found Aug 28, 2021
    View case
    Sex ✓Male
    Age 100%Est. 30–45 vs 45 when missing
    Race 100%White
    Location 72%113 mi away, same state
    TimingFound 33 years after last seen
    Height 100%5'9" vs 5'8"
    Weight 87%150 lb vs 180 lb
    Hair 100%Brown vs Brown
    75%Possible
    John Doe — Detroit, Michigan - unidentified case UP11702
    John Doe — Detroit, Michigan
    UP11702 • Found Nov 22, 2007
    View case
    Sex ✓Male
    Age 100%Est. 35–45 vs 45 when missing
    Race 100%White
    Location 74%106 mi away, same state
    TimingFound 19 years after last seen
    Height 100%5'9" vs 5'8"
    Weight 100%179 lb vs 180 lb
    Hair 100%Brown vs Brown
    Eyes 0%Blue vs Brown

    These comparisons are generated automatically from public NamUs case data and are not confirmed identifications. Only DNA, dental or fingerprint comparison by investigators can confirm an identity. If you believe two cases are connected, contact the agency handling the unidentified case.

    Unidentified photos are blurred because many are post-mortem. Tap a photo to reveal it.

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    Forum Posts (1)

    Mark O’Neill was 45 when he disappeared from Harbor Beach, Michigan, on October 16, 1988. He was... ...Read More
    02/14/2024

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