NEW YORK -- Top Soviet leaders considered Andrei Sakharov so dangerous that the Kremlin figured he must be receiving orders from Western intelligence agencies, according to KGB files.


In the trove of formerly top-secret documents released Wednesday, the KGB depicted Sakharov -- the human rights advocate exiled by the Kremlin and awarded a Nobel Peace Prize by the West -- as psychologically fragile and a dupe of his wife and foreign agents.


For many years, Sakharov challenged Soviet power by advocating nuclear disarmament, criticizing Soviet foreign policy and publicizing human rights abuses. The files illustrate how much fear one man could inspire at the top echelons of the one-time superpower.


"Sakharov's behavior does not often correspond to the accepted norms," says one document, a memo to the Communist Party Central Committee dated Aug. 26, 1980, and signed by then-KGB chief Yury Andropov. "It is excessively prone to the influence of people who surround him, his wife above all, and it patently violates common sense."


The memo quotes Soviet psychiatrists diagnosing Sakharov as "a pathological personality, which is common in families with hereditary schizophrenia." It also asserts that his wife, Yelena Bonner, received instructions from U.S. intelligence services.


"It has been established that Bonner's activities, which feed the anti-Sovietism of her husband, not only are based on her hostile attitude to the Soviet system but also correspond to the instructions of intelligence services in the U.S.A. and other foreign anti-Soviet centers," the memo states.


Family members and Brandeis University officials who released excerpts of the files said the documents reveal how deeply Soviet leaders feared and reviled Sakharov. "They are a unique record of the length the Soviet Union was willing to go to harass a man they considered to be Enemy No. 1 of a totalitarian state," Jehuda Reinharz, president of Brandeis University, said at a news conference to release the documents publicly.


Sakharov, a nuclear physicist who was awarded the Nobel Peace Prize in 1975, was exiled from Moscow after criticizing the 1979 Soviet invasion of Afghanistan. He was released in 1986 by former Soviet president Mikhail Gorbachev and served in the Russian Parliament before his death in 1989.


The documents released Wednesday are a sample of 70 KGB files turned over to Bonner last May in a ceremony in Moscow. At that time, the head of the counterintelligence service, Sergei Stepashin, noted they were a fraction of the estimated 520 volumes of material compiled on Sakharov by the KGB.


Tatyana Yankelevich, Sakharov's stepdaughter, told reporters that most of the 70 files consist of memos to the Central Committee from 1967 to 1990. They include documents signed by each KGB chief in that period, including Andropov, who succeeded Leonid Brezhnev as Communist Party chief in 1982.


Yankelevich said one of the most surprising aspects of the dossier is that it lacks any suggestion or nuance that the allegations are fabricated.


"It was a representation of reality as they saw it," she said.


Natan Scharansky, a Sakharov friend and fellow dissident, said the documents reveal the seamlessness of Soviet government deception. Even top-secret reports prepared for a small circle of decision-makers used the same ideology-laden language as propaganda aimed at the party rank-and-file.


"Those who wrote these memos, their job was to create reality. Members of the Politburo accepted it as fact," Scharansky said. "How could these people analyze reality if they were deceiving themselves?" Scharansky said the documents also make it clear that the KGB was preparing legal documentation to support further action against Sakharov, including arrest, imprisonment or internment in a psychiatric hospital.


Bonner worked for years to gain access to the files. She has been told that some or all of them were destroyed in 1990, a claim she doubts. Yankelovich said her mother would continue to press for the release of more of the KGB files.