A New York City man has pleaded guilty to manslaughter in the murder of an 81-year-old World War I veteran several decades ago, officials said.

Martin Motta, 75, from Queens, faces 20 years in prison for the 1976 killing of George Clarence Seitz. Motta will be sentenced on Nov. 7, according to a press release from the Queen's District Attorney's Office.

Seitz disappeared from his Jamaica, Queens home on Dec. 10, 1976, after he left to get a haircut and never returned.

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Seitz's disappearance became an unsolved missing persons' case for more than 40 years until a New York Police Department (NYPD) detective received a tip about the murder.

Authorities said the veteran’s remains were found in March 2019, buried under concrete in the backyard of a Richmond Hill home. The body had been dismembered at the neck, shoulders, and hips, officials said.

Initially, a DNA profile of the remains did not lead to an identification, but in February 2021, a private lab determined a genealogical profile that authorities used to identify the victim as Seitz.

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This was the first time a city prosecutor used forensic genetic genealogy in a homicide case, Queens District Attorney Melinda Katz announced in the press release.

Human Remains

Authorities found human remains in 2019 in a backyard in Queens. (Queens District Attorney's Office)

"No matter how much time has passed, we will use every tool at our disposal to achieve justice." Katz said. "For the gruesome murder of a World War I veteran, the defendant eluded arrest for more than 46 years. Now he is headed to prison thanks to the collaboration between the NYPD and our Cold Case Unit."

Detectives believe Motta targeted the war veteran because the victim was known to carry large sums of cash while strolling through the neighborhood.

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The investigation revealed that after Motta had fatally stabbed Seitz, he stole approximately $7,000-$8,000 from his person. The NYPD and the Queen's District Attorney's Office said that the extensive investigation included several eyewitnesses and a record search that spanned five states.