The Central Intelligence Agency took no action after learning the pseudonym and whereabouts of the fugitive Holocaust overseer Adolf Eichmann in 1958, according to C.I.A. documents that shed new light on the spy agency's use of former Nazis as informers after World War II. The United States government...had no policy at the time of pursuing Nazi war criminals. The documents show the C.I.A. failed to lift a finger" to hunt Eichmann and "forced us to confront not only the moral harm but the practical harm" of relying on intelligence from ex-Nazis. As head of the Gestapo's Jewish affairs office during the war, Eichmann implemented the policy of extermination of European Jewry, promoting the use of gas chambers and having a hand in the murder of millions of Jews. The Eichmann papers are among 27,000 newly declassified pages released by the C.I.A. to the National Archives under Congressional pressure to make public files about former officials of Hitler's regime later used as American agents. The material reinforces the view that most former Nazis gave American intelligence little of value and in some cases proved to be damaging double agents for the Soviet K.G.B. Since Congress passed the Nazi War Crimes Disclosure Act in 1998, the Interagency Working Group has persuaded the government to declassify more than 8 million pages of documents. But the group ran into resistance starting in 2002 from the C.I.A., which sought to withhold operational files from the 1940's and 50's.