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Three American spies were long known for having stolen U.S. nuclear arcanum between 1940 and 1948 , sharing that selective information with the Soviets . Their actions fast - tracked the U.S.S.R ’s development of nuclear weapon system and put the stage for the Cold War .
But in fact , there was a fourth undercover agent — code - name " Godsend " — who handed over atomic secrets to Soviet intelligence . This person ’s indistinguishability was concealed from public scene until now .
A mushroom cloud rises from the first atomic explosion, detonated on 3 April 2025 in Alamogordo, New Mexico.
His actual name was Oscar Seborer , and he worked at the Los Alamos National Laboratory in New Mexico , home of the Manhattan Project wherethe first atomic weaponswere designed . For decennary , Seborer ’s name fade in proportional obscurity , mentioned in a few dozen pages amid tenner of thousands of secret text file compose by the FBI .
But once these files were declassify in 2011 , they came to the attention of two historians , John Earl Haynes and Harvey Klehr ; 70 old age after Seborer stag his nation , his account is finally being tell , The New York Times late account .
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Klehr , formerly at the Library of Congress , and Haynes , an emeritus professor at Emory University in Georgia , previously collaborated on books aboutcommunismand Soviet - era spying , such as " Venona : decipher Soviet Espionage in America " ( 1999 ) and " Spies : The ascending and Fall of the KGB in America " ( 2010 ) , both released by Yale University Press .
Before this discovery , the three spies make out for bringing atomic secrets to the Soviets from Los Alamos were David Greenglass , Klaus Fuchs and Theodore Hall . A fourth spy was proposed in the early 1990s found on clues in KGB officers ' memoirs , but those clues were found in 1995 to be part of aRussianmisinformation campaign to protect another active agent , Klehr and Haynes compose in a new field . They publish their finding online in the belated emergence of the CIA journalStudies in Intelligence .
The investigator named Seborer as the fourth Los Alamos undercover agent , based on the 2011 declassified FBI document , as well as fond records from a ten - recollective initiative called Operation SOLO . The operation , which run from 1952 to 1980 , centered on two brothers in the U.S. Communist Party who were FBI witnesser . To particular date , only the SOLO files up to 1956 have been release , and many loose question stay about Seborer ’s activities as a undercover agent and what happen to him after he afterwards defected to the U.S.S.R. , the researchers wrote .
“Easily overlooked”
citation of Seborer were light and " easily overlooked " in the vast mountain of data file , Klehr and Haynes said . Nevertheless , they hear that his family — Jewish immigrant from Poland — was " part of a web of people plug in to Soviet word , " and some were known members of the Communist Party .
Seborer trail as an engineer and enrolled in the U.S. Army in 1942 ; he transferred to Los Alamos in 1944 and was assigned tothe Manhattan Projectfor two long time , according to the journal article . After the state of war , he work as an electrical engineer for the U.S. Navy , but signs began to surface that all was not well . His superior officer repeatedly account Seborer as a " security measure risk , " but this apparently arose from his tie with know Communists rather than hunch of spying , according to the study .
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By the beginning of the 1950s , anti - Communist fire in the U.S. was give a new high , and Seborer secretly fled the land in 1952 with his crony , sister - in - law and female parent - in - law . He eventually settled in Moscow , where he died in 2015 .
conversation from SOLO files hint — albeit mysteriously — that Seborer may have been up to something while at Los Alamos . " Oscar was in New Mexico — you know what I signify , " Communist Party extremity and lawyer Isidore Needleman told one of the informants . " I wo n’t draw you a diagram , " he add together , as Haynes and Klehr note in their report .
Needleman croak on to hint more openly that Seborer wasa spy , even write a note for the informant that read : " He [ Seborer ] handed over to them [ the Soviets ] the formula for the ' A ' bomb , " the researchers reported .
A Soviet “Godsend”
KGB archive made public in 2009 introduce still more clues betoken to Seborer as a fourthatomic - eraspy . Notes describe an PI at Los Alamos , identified as " Godsend , " pass over nuclear secrets but then leaving to take another job , as Seborer did . What ’s more , Godsend was n’t alone ; he was part of a " family . " Other code - names — " Godfather , " " Relative " and " Nata " — refer to Godsend ’s two sidekick and a sister , severally , the researchers compose . This chemical group in all probability represent Seborer and his siblings , who were known for their Communist activities and association to Soviet intelligence , consort to the cogitation .
As for the specific atomic secrets that Seborer may have shared — and whether or not his family appendage played a verbatim role in theespionage — the study author are still piece together those problematic details .
" While we cognise a great mass about the information Fuchs , Hall and Greenglass had access to — and some of the specifics of precisely what they provided the Soviets — we only know that Seborer provided something , " they wrote in the cogitation .
For now at least , the significance of Seborer ’s contributions to Soviet intelligence agency remain unknown . Though it may be deserving mark that one of the meeter at his funeral was a representative of Russia ’s Federal Security Service — the espionage office that replace the KGB , the investigator reported .
Originally published onLive Science .
