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Mark Seifert Missing Person Case

Last seen in Machias, New York on Feb 13, 1984

Victim Details

Mar 09, 2011

Jun 07, 2022

Mark

Seifert

73

31

71 inches

145 lbs

White / Caucasian

Male

Feb 13, 1984

Machias

New York

Cattaraugus County

9779

New York State Police - Machias

Machias

New York

Cattaraugus County

14101

9761 New York 16, New York

7163534029

State

Law Enforcement

SJS 3029407

New York State Police - Machias

Brown

Brown

Brown

07/21/2026


Area Last Seen:

Case Description

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Mark Seifert, 31, was last seen on February 13, 1984, in Machias, New York. His vehicle was later discovered burning on a rural road, but Seifert himself was nowhere to be found. Investigations revealed that Seifert's brother, William Seifert, lured Mark to a remote location under the pretense of a construction job. William was later convicted of Mark's murder, despite Mark’s body never being located. Evidence presented during the trial indicated that William had a deep animosity tow ...
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Last Seen: Feb 13, 1984

Links to Additional Sources (3)

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  • Cold Case Files - Buffalo News
  • February | 2024 | Another Bundy Blog.
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    Forum Posts (2)

    I’ve been following the Mark Seifert case for years, and something that’s stuck with me is the l... ...Read More
    12/03/2023
    Has anyone here ever looked into why Mark Seifert’s body was never found, despite the conviction o... ...Read More
    03/25/2023
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