The allegations come as former co-workers and intelligence experts say veteran FBI figure Robert Philip Hanssen left a trail of clues that led authorities to arrest him and charge him with spying for Moscow.
Russian documents and letters that Hanssen allegedly sent to his Soviet handlers contained hints of his identity - from his code name "B" (Hanssen went by Bob) to using the name of his hometown Chicago as a signal, these former associates said in interviews.
FBI officials would not publicly discuss how they came to pinpoint Hanssen as the agent whose alleged spying activities were detailed in internal Russian documents they obtained.
"He increased his chances of getting caught" said Paul Moore, a former FBI counterintelligence analyst who has known Hanssen for 20 years.
Until Hanssen was targeted by the FBI last year, federal investigators focused on a CIA agent who may now be cleared because of Hanssen's arrest, the Washington Post reports.
The CIA official has been suspended on paid leave for the past 18 months, the newspaper said in a report Friday. He had passed several polygraph tests and some officials told the Post the evidence against him was marginal.
An intensive search for spies began in 1994 when CIA officer Aldrich Ames pleaded guilty of spying for the KGB, the newspaper said. But there may have been loopholes in the investigation.
On one occasion, Hanssen was caught at FBI headquarters breaking into the computer of Ray Mislock, then supervisor of an agency unit responsible for Russian counterintelligence, sources told the Times.
Moore said Hanssen was never plygraphed. The FBI has declined to comment on whether Hanssen took the test. Not only that, Hanssen was meticulous about checking to see whether the bureau was aware of his activities, FBI officials have said.
The counterintelligence sources questioned by the Times said the unwillingness of FBI director Louis Freeh to use polygraphs more widely probably made it easier for Hanssen to escape detection.
FBI officials have said that Hanssen's identity was not known to the Soviets. The letters and documents about Hanssen refer to him as "B". But these documents had details about the information that Hanssen was accused of leaking, which the FBI could then use
to narrow its search.
"They had a lot to work with," said Richard Alu, a retired FBI counterintelligence agent who worked with Hanssen for several years.
The FBI said Thursday that tighter controls over top-secret documents, and other improvements recommended after the Aldrich Ames spy case, helped it to apprehend Hanssen, a 20-year FBI countintelligence agent accused of passing top-secret information to the Soviets and Russian for 15 years.
Bureau management had been cautioned four years ago by the Justice Department inspector general to enhance training and communications. The FBI was criticized at the time by the Justice Department inspector general for not doing enough to find out how Ames leaked sensitive information to the Soviet Union. Ames pleaded guilty in 1994.
FBI spokesman John Collingwood said recommendations made in the inspector general's 1997 report were implemented and had a direct bearing on the arrest of Hanssen.
"The IG's recommendations were constructive and incorporated into the FBI's counterespionage program," Collingwood said. "The post-Ames focus on the possibility of additional compromises led directly to the charges against Hanssen. Substantial resources and expertise are being afforded to this effort."
Despite the improvements, Hanssen's spying went undetected for 15 years.
Several current and former intelligence officials told the Times the fact that Moscow had penetrated the U.S. government was known for several years, but not acted upon. The sources said the conclusion was drawn from a series of unrelated cases, including the 1989 espionage case of State Department employee Felix S. Bloch and failures of intelligence operations against the Russians.
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