GENESEE TWP. (WWJ/AP) – Prosecutors say a long-imprisoned killer whose DNA was linked last year to a decades-old killing of a Flint-area woman has agreed to a plea deal.

Genesee County Prosecutor David Leyton last year charged 43-year-old Mathew L. Alder with first-degree murder in the November 1993 killing of 19-year-old Wanda Musk. Alder is already serving life in prison for a 1994 murder in Roseville.

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Alder pleaded guilty Wednesday to second-degree murder, with an agreement that he get 20 to 30 years in prison. He told the judge he beat Musk to death with a steel baton.

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Authorities found Musk’s naked body along a road in Genesee Township. They say the Mott Community College student was last seen alive with a man who had his arm around her at a store where she worked.

The DNA match came under a new state law requiring testing of prisoners. Inmates previously weren’t required to provide a DNA sample until being released or placed in a halfway house.

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