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Case Description
Any updates on this case?
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 toward Mark, ...Read More
Last Seen: Feb 13, 1984
Last Seen: Feb 13, 1984
Links to Additional Sources (5)
See any mistakes?Victim Details
Mar 09, 2011
Jun 07, 2022
Mark
Seifert
72
31
71 inches
145 lbs
White / Caucasian
Male
Feb 13, 1984
Machias
New York
Cattaraugus County
345
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
11/22/2025
Area Last Seen:
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
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
03/25/2023
