Alan Spearman / AP

Al Williams, left, and Calvin Jackson remove tombstones that came from the Memphis National Cemetery from the Midtown back yard of Jason Blackburn in Memphis on Tuesday, May 22, 2012.

An official looking into the case of tombstones found by a man gardening in his midtown Memphis backyard says seven more markers have been uncovered.

Jason Blackburn first found 13 headstones while clearing a path to his dog’s pen over the weekend.

Raymond Miller, director of the Memphis National Cemetery and the national cemeteries in Little Rock and Corinth, Miss, said the headstones were removed between July 5, 1970, and Dec. 28, 1970, when the U.S. Army operated the historic memorial park. They were replaced by newer grave markers that include the names of more recently deceased relatives.

Tennessee man digging in garden finds 13 tombstones linked to military cemetery

While digging up the headstones Tuesday for their return to the military cemetery, seven additional markers were discovered, pushing the number found to 20, Miller told msnbc.com.

The cemetery is now run by the Department of Veterans Affairs.

It remains unclear how the old headstones made their way some six miles to the central Memphis neighborhood.

A former Memphis city councilman who once owned the house told the Commercial Appeal he was told by a real estate broker the headstones came from a cemetery worker who once lived there.

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"I was told he would bring home the ones they messed up when they were engraving them,” Jack Sammons told the newspaper. “It's a granite marker, not like an Etch A Sketch, I guess. You couldn't just wipe 'em clean."

Miller told msnbc.com that the found headstones will be destroyed after it is verified that all of the headstones have been replaced by subsequent markers.

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Alan Spearman / AP

Al Williams, left, and Calvin Jackson remove tombstones that came from the Memphis National Cemetery from the Midtown back yard of Jason Blackburn in Memphis, May 22. No one knows how they came to be in Blackburn's backyard used as stepping stones, but after he discovered them buried there by years of leaf debris, Blackburn contacted the cemetery and had them returned.

A Tennessee man digging in his backyard garden over the weekend found 13 tombstones that have been traced to a historic military cemetery.

Jason Blackburn, a nurse at the Baptist Memorial Hospital for Women in Memphis, was clearing a walkway that leads to his dog’s pen when he dug up a tombstone below some 3 inches of dirt. At first he mistook it for a garden stone, the Memphis Commercial Appeal reported.

“My first reaction was, ‘Oh my goodness, I hope there’s not dead bodies in my backyard,” Blackburn told the newspaper. “I mean that’s the first reaction when you’re digging in your backyard and you find tombstones.”

Blackburn searched a name on one of the gravestones -- Pvt. Arthur Woodson -- on the Internet and determined it was linked to Memphis National Cemetery, a historic memorial park that goes back to the Civil War and is now run by the Department of Veterans Affairs.

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Raymond Miller, director for Memphis National Cemetery and the national cemeteries in Little Rock and Corinth, Miss., told msnbc.com that VA workers were heading over to Blackburn’s home on Tuesday to inspect the tombstones. He said the time the markers went missing has been narrowed down to a four-month period in 1970. It is believed the markers are from the 1960s.

“This is government property,” Miller told msnbc.com. “We’re going to retrieve them and look to see what information they have.”

He said the stones include markers for veterans, spouses and even a young child. The found gravestones are “old headstones” that have been replaced by newer markers after the death of a spouse or child, he said.

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Still, it’s unclear how they ended up in someone’s backyard. Old headstones are typically destroyed after they are replaced, Miller said.

The discovery comes months after a VA audit found 123 burial problems at military cemeteries across the country, and after more than 200 graves at Arlington National Cemetery were found to be unmarked or misidentified, leading to a congressional probe and criminal investigation. The Memphis National Cemetery wasn't implicated in the VA report.

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