HUDSON, Mich. (AP) – Crews digging for gravel in southern Michigan have found skeletal remains including a human skull.

State police responded on Thursday following the discovery near Hudson, about 75 miles southwest of Detroit, and determined that the bones likely are too old to be connected to a recent death.

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WILX-TV reports forensic teams were called in, including anthropologists from Michigan State University, and the remains may be 400 to 1,000 years old.

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State police say the remains at the site in Jackson County’s Pittsford Township are believed to be from a Native American man.

The Hillsdale Daily News reports human remains previously found in the area were attributed to a possible former graveyard.

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