David Greenglass, an American spy who passed nuclear secrets to the Soviet Union in one of the most high-profile espionage scandals of the Cold War, has died at the age of 92.

David Greenglass stole atomic research data while working on the wartime Manhattan Project in Los Alamos, New Mexico.

After being arrested he then lied on oath and gave evidence which sent his own sister to the electric chair.

David Greenglass’s death was in July but it has only now been reported.

A native New Yorker, David Greenglass secured a role on the Manhattan Project after being drafted into the army following the outbreak of World War Two.

Manhattan Project was America’s top secret attempt to develop the world’s first nuclear weapon.

David Greenglass was an American spy who passed nuclear secrets to the Soviet Union in one of the most high-profile espionage scandals of the Cold War (phoot Wikipedia)

David Greenglass, a young convert to Communism, began passing highly classified information to his brother-in-law, Julius Rosenberg – a Soviet spy who was married to his sister Ethel.

After being arrested in 1950, David Greenglass testified that during one meeting with Julius Rosenberg he had seen Ethel typing up notes.

Speaking to a reporter years later, David Greenglass admitted that he had lied in order to save the life of his own wife Ruth, who had also been arrested after attending the same meeting.

Over the following years serious doubts began to emerge about Ethel Rosenberg’s execution.

“As a spy who turned his family in… I don’t care. I sleep well,” David Greenglass told the journalist in 2001.

The Rosenbergs were both executed for treason. David Greenglass, meanwhile, served 10 years of a 15-year sentence for espionage and was released in 1960.

David Greenglass died in New York City on July 1, according to the Rosenbergs’ sons, Michael and Robert Meeropol.

Michael and Robert Meeropol were aware of the death earlier but did not seek media attention.

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