Original sentence: However, the newly-released declassified CIA documents confirm the accuracy of Powers' report.In 2010, CIA documents were released indicating that American officials did not believe Powers' account of the incident at the time, because it was contradicted by a classified National Security Agency report.The NSA report remains classified.The exchange was for Soviet KGB Colonel Vilyam Fisher, generally known as "Rudolf Abel", who had been caught by the FBI and jailed for espionage
Edited sentence: According to the article cited, the still classified NSA report is incorrect based on the CIA documents that were declassified which show that Powers' account of being shot down at altitude was accurate.For it is now possible to piece together what really happened high over Sverdlovsk on May 1, 1960, and to understand why America’s most secretive intelligence agency got it so wrong".In 2010, CIA documents were released indicating that "top US officials never believed Powers’ account of his fateful flight because it appeared to be directly contradicted by a report from the National Security Agency, the clandestine US network of codebreakers and listening posts.The NSA report remains classified, possibly to spare the blushes of its authors.The exchange was for Soviet KGB Colonel Vilyam Fisher (aka Rudolf Abel), who had been caught by the FBI and jailed for espionage