In fact, Italian intelligence officials knew what had happened: Yurchenko, 50, one of the highest-ranking agents in the KGB, the Soviet intelligence organization, had defected to the West. He has reportedly been sequestered somewhere in the U.S. for the past six weeks, undergoing debriefing by the CIA. Reagan Administration officials said that Yurchenko has provided details of KGB operations in Europe and the U.S. and information about the "spy dust" that Soviet secret police allegedly used to track Americans in Moscow. He has also fingered as many as six former CIA agents who worked as "moles" for the Soviet Union. Some of them apparently quit the agency in the past few months and fled to Moscow. The CIA has denied publicly that any of its current employees have been named as double agents.
Yurchenko is believed to be the most senior KGB defector since the 1930s, when two generals in the Soviet intelligence service fled the U.S.S.R. during Stalin's purges. He was a top-ranking member of the KGB's first chief directorate; specifically, he was assigned to the K directorate, which is responsible for penetrating other intelligence services. From 1975 to 1980 he served in Washington as a first secretary at the Soviet embassy and presumably had knowledge of Soviet agents and moles in the U.S. After returning to Moscow, says one intelligence source, he handled liaison between the KGB and the Central Committee of the ruling Politburo. "It's caused a real body blow to the KGB," said Patrick Leahy, a member of the Senate Select Committee on Intelligence, of Yurchenko's defection. "They must be in sheer panic over there."
Yurchenko's defection sent a major shock wave through the mysteriously intertwined network of East-West espionage, which has been vibrating all summer with a series of defections and reactions. Three weeks after Yurchenko's disappearance, Hans Joachim Tiedge, a senior official at West Germany's counterintelligence agency, called in sick. Four days later East Germany announced that Tiedge, who had been responsible since 1981 for detecting East German spies in his country, had gone over to the other side. Although he was in debt and had a drinking problem, some Western experts suspect that Tiedge feared exposure as a result of Yurchenko's defection.
If Tiedge had worked for any length of time as a Soviet mole, he could have protected East German spies and endangered the cover of West German ones. A week after Tiedge's flight, Martin Winkler, a Buenos Aires-based East German diplomat who was probably a double agent, came in from the cold and sought asylum in West Germany.
A trio of spies who may have worked with Tiedge are also believed to have followed him to East Germany. A 61-year-old woman using the false name Sonja Luneburg disappeared last August after serving for twelve years as secretary to Martin Bangemann, the West German Minister of Economics. Another woman living under an alias, Ursula Richter, 52, worked as a bookkeeper for a Bonn- based lobbying group for German refugees from Poland, Czechoslovakia and the U.S.S.R. She also vanished last summer.
When police searched the apartments of the missing women, they found several tools of the spy trade, including camera equipment that could be used to photograph documents and a briefcase with a secret compartment. West German authorities think that a third possible spy, a friend of Richter's named Lorenz Betzing, may have also fled eastward. She once worked for a firm that installed air conditioning at a military hideout built to serve as an emergency command center in case of war.
Last month the KGB's senior agent in London, Oleg Gordievsky, defected after years of providing the British with intelligence on Soviet espionage operations. Within a week the British government dismissed 31 Soviet diplomats, trade officials and journalists whom the double agent had identified as spies. Moscow, clearly embarrassed by the incident, retaliated by expelling an equal number of British citizens.
Reagan Administration officials last week confirmed another coup: Sergei Bokhan, deputy director of Soviet military intelligence in Athens, had ^ defected in May. Bokhan has provided information about the extent of Soviet infiltration of the Greek military, which may explain why the U.S. postponed a sale of 40 F-16 fighter jets to that country.
One recent disappearance remains unresolved. Vladimir Alexandrov, a prominent Soviet physicist, vanished without a trace while visiting Madrid late last March. Alexandrov originated the mathematical model for the nuclear winter theory, which holds that the smoke and dust hurled into the atmosphere by a full-scale nuclear war between the superpowers would block the sun's rays for weeks, causing the earth's temperature to plummet. The mystery of his disappearance has been compounded by the suspicions of some Western scientists that the nuclear winter scenario was promoted by Moscow to give antinuclear groups in the U.S. and Europe some fresh ammunition against America's arms buildup. Conspiracy theorists speculate that Alexandrov was planning to renounce the nuclear winter concept and may have been kidnaped by the KGB. According to another theory, the physicist defected to the West. In any case, a delegation of Soviet scientists skipped an annual conference in Sicily this summer, giving neither an explanation nor an advance warning of the boycott.