Neighbors said William and Patricia Wycherly, who lived in the house in Forest Town in the 1990s, disappeared in 1998, the Nottingham Post reported.
Police said Tuesday they were investigating what they believe to be a double homicide. The remains were found last week in the back garden.
An anthropologist who examined the skeletons determined one was a man of at least 60 and the other a woman older than 40, police said. The female skeleton had a physical anomaly in common with Patricia Wycherly.
Police said the couple, 85 and 62 when they were last seen, lived quietly in Forest Town, a former mining village outside Mansfield and about 12 miles north of Nottingham.
Detective Chief Inspector Rob Griffin said investigators have talked to relatives of William Wycherly and friends of the couple, and have been trying to trace Patricia Wycherly's relatives.
"The historic nature of the inquiry means it is a long and complex process," Griffin said. "But we are determined to get to the bottom of who was buried in the garden, how they got there and for what reason."
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