Marcus Klingberg, an Israeli scientist and the highest-ranking Soviet spy ever caught by the Israeli security services, which regarded his activities as so damaging that they imprisoned him in secret under a false identity and barred the Israeli news media from writing about certain aspects of his case for 25 years, died on Monday in Paris. He was 97.
His grandson, Ian Brossat, confirmed the death to The Associated Press.
Mr. Klingberg, an epidemiologist who had served with the Red Army Medical Corps during World War II after fleeing his native Poland, emigrated to Israel in 1948. There, after serving in the medical division of the Israel Defense Forces, he began working in 1957 for the Institute for Biological Research, a top-secret chemical and biological-weapons laboratory at Ness Ziona, near Tel Aviv.
A committed communist, Mr. Klingberg passed information about the lab’s research to the Soviet Union. Using the Russian code name Rok, meaning fate, he arranged meetings with his handler, “Victor,” by leaving coded chalk marks on a wall in Tel Aviv. Meetings were held over vodka and caviar in the back room of a Russian Orthodox Church. On one occasion, in recognition of the value of his work, he was secretly awarded the order of the Red Banner of Labor, the Soviet Union’s second-highest honor.
Twice, in 1965 and 1976, Mr. Klingberg was brought in for questioning by suspicious security officers, only to be released, passing a polygraph test on one occasion.
In the early 1980s, however, a double agent exposed him. Shin Bet, Israel’s internal security agency, devised a ruse to capture him. Mr. Klingberg was invited to join an official mission to Singapore, where a chemical plant had exploded and his expertise was needed. He agreed. Instead of being driven to the airport, he was taken on Jan. 19, 1983, to a secret location in Tel Aviv, where, under interrogation, he admitted to spying for the Soviet Union.
Found guilty of espionage by a military tribunal, Mr. Klingberg was given the maximum prison sentence of 20 years. After being assigned a false name, Abraham Grinberg, and a false title, editor of a social-science magazine, he was sent in secret to the high-security prison Ashkelon to begin his sentence.
After serving nearly 16 years, the first 10 in solitary confinement, Mr. Klingberg was paroled and placed under house arrest. It was not until 1993, after the collapse of the Soviet Union, that the Israeli authorities admitted that he had been imprisoned. In 2003, after completing his sentence, he was allowed to emigrate to France to be near his family on the condition that he never speak about his work at Ness Ziona. A gag order by military censors prevented the Israeli news media from fully writing about the case until 2008.
Mr. Klingberg remained unrepentant. “I didn’t think of myself as a spy; even today I don’t consider myself a former spy,” he wrote in his memoir, titled, nonetheless, “The Last Spy.” Written with his lawyer, Michael Sfard, it was published in 2007.
Mr. Klingberg insisted that he had spied for ideological reasons, and out of a belief that all information about weapons should be shared among nations. He insisted that he had received no money from the Soviet Union for his services.
Sylvia Klingberg, his daughter, told the news agency Agence France-Presse after his death, “He was a communist who acted out of conviction and gratitude to the Red Army for having allowed him to fight the Nazis who massacred his entire family in Poland.”
Avraham Mordechai Klingberg, known as Marek or Marcus, was born on Oct. 7, 1918, in Warsaw into a family of ultra-Orthodox Jews. He embraced a secular life as a teenager and studied medicine at the University of Warsaw.
Heeding the warnings of his father, he left Poland after the outbreak of World War II. “At least one has to remain alive,” his father told him, he wrote in his memoir. “You have to go.” In 1942, his parents and younger brother were transported to Treblinka, where they died.
He completed his medical studies in Minsk, then part of the Soviet Union, training as an epidemiologist.
He volunteered to serve in the Red Army on the day that Germany invaded Russia. Holding the rank of captain in the medical corps, Mr. Klingberg served on the front lines until he was wounded by shrapnel in his right leg. After he recovered, he led an anti-epidemic unit in Molotov (now Perm), near the Urals, where outbreaks of typhus were a constant threat.
As the Red Army advanced west in 1943, he was named chief epidemiologist for the Byelorussian republic (now Belarus). He returned to Poland after the war, where he learned the fate of his parents and younger brother.
He found work as an epidemiologist for the ministry of health and married Adjia Eisman, a microbiologist who had adopted the name Wanda Yashinskaya. In 1946, they emigrated to Sweden.
Mr. Klingberg’s wife died in 1990. His daughter, Sylvia, joined the revolutionary anti-Zionist movement Matzpen in Israel and, after emigrating to France, became a communist activist. Her son, Ian, is a member of the French Communist Party and serves on the Paris City Council.
After emigrating to Israel, Mr. Klingberg rose to the rank of lieutenant colonel in the Israel Defense Forces, holding senior positions in the division of preventive medicine in the office of the surgeon general. He was part of a team that published early work on West Nile fever.
In 1953, he was appointed director of the military’s medical research laboratories, and in 1957, he left the army to become the deputy scientific director of the Institute for Biological Research.
After spending two years on sabbatical at the Henry Phipps Institute at the University of Pennsylvania in the early 1960s, Mr. Klingberg turned his attention to noninfectious epidemiology, specifically congenital malformations caused by thalidomide, and disasters like the mass exposure to dioxin at Seveso, Italy, in 1976.
In 1974, he helped organize an international clearing house to monitor birth defects. In addition to working at Ness Ziona, he taught epidemiology and led the department of preventive and social medicine at the Sackler Faculty of Medicine at Tel Aviv University.
Mr. Klingberg told his interrogators that he had been recruited as a spy in 1957, after Soviet agents threatened to ruin his career by revealing that he had never completed work for a medical degree.
But in his memoir, he wrote that he began spying in 1950. Israeli intelligence officers strongly suspected that he was already a Soviet agent when he emigrated to Israel. He also revealed in his memoir that he had recruited his wife, who was a microbiologist at the institute, as well as two friends, to spy for the Soviet Union.
“I have never regretted my modest attempt during the Cold War to undermine what I believed to be the dangers associated with imbalances in scientific knowledge,” Mr. Klingberg wrote in an article for The Journal of the Royal Society of Medicine in 2010.
“My feelings about this remain with me despite the fall of the Soviet Union, a country to which not only I owe my life, as well as my career in epidemiology and my most useful work; but, above all, the opportunity to fight fascism.”
Correction: December 4, 2015
An earlier version of this obituary misstated when a double agent exposed Mr. Klingberg. It was the early 1980s, not the early 1960s.