Derek Michael Mason was last seen leaving his South 39th Street home in October of that year, according to troopers.
His remains were discovered off the Pennsylvania Turnpike in Clay Township, Lancaster County in January 1992. Authorities determined that he had been murdered, but it took until 2023 to identify him using DNA evidence, police say.
Mason was known by the nicknames "Hawkeye" and "Hawk."
State police said there is an upcoming block party in Mason's old neighborhood and hope that the "many people returning to the area for the festivities may (...) have information in this case."
To report a tip, call Trooper Brian McNally of PSP Lancaster at 717-290-1967. A $2,000 reward is offered.
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