The Pickaway County, Ohio, sheriff and attorney general announced on Tuesday that human remains discovered 31 years ago have been identified as Robert A. Mullins of Columbus.

Hunters discovered the skeletal remains in a shallow grave next to a private farm on State Route 56 in Pickaway County, on Nov. 1, 1991.

At first, the remains were thought to be those of an Indigenous American, a press release from Ohio Attorney General Dave Yost stated, but after a further investigation conducted by anthropologists, the remains were much newer.

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Through their investigation, anthropologists determined the remains had been in the ground no more than three years and could be those of a woman approximately 25-years-old, between 5-foot-1 and 5-foot-4 inches.

"Thirty-one Christmases have gone by while this family waited for answers," Yost said in the press release. "When the results weren’t immediate and the case grew cool, Pickaway County law enforcement dug in their heels and kept trying until the evolution of DNA technology finally yielded an identity for John Doe."

Pickaway County Sheriff’s Office investigators continued to seek answers to who the remains belonged to over the next 31 years, with the help of the county coroner’s office as DNA technology advancements opened more possibilities.

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For instance, scientists at the University of North Texas evaluated the remains in 2012 and determined the individual was a male.

Seven years later, the Bureau of Criminal Investigation in Ohio opened an unidentified human remains case after being asked for assistance by the coroner’s office. As a result, enough DNA from the bones was extracted for more advanced testing.

The focus was then turned to genetic genealogy in 2021 to identify who John Doe was.

In January 2022, the sheriff’s and coroner’s offices had the DNA profile uploaded into DNA matching databases.

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A strong lead on the identity of John Doe came through on Nov. 1, 2022, 31 years from the date that the remains were found.

Investigators consulted with Mullins’ family and obtained DNA samples, which provided the data needed to verify his identity.

"Mullins’ family reported that he went missing in late 1988 or early 1989 at age 21," the press release read. "He was 5 feet 3 inches and lived on the northeast side of Columbus."

Although the bones have been matched to Mullins, the sheriff’s office still has an open homicide investigation on the case.

The sheriff’s office encourages anyone with information about the case to call Lt. Jonathan Strawser at 740-474-2176.