Authenticity
U.S. official sources, including the U.S. House Intelligence Committee, and the U.S. State Department, maintain that it is a forgery. A KGB defector testified before the U.S. Congress that it was a forgery of Soviet origin. The Danish Defense Intelligence Service (DDIS) concluded in 1976 that the forgery was part of a disinformation campaign waged by the KGB.
The discovery in the early 1990s of the Operation Gladio (NATO stay-behind networks) in Europe led to renewed debate as to whether or not the manual was fraudulent. The former deputy director of the CIA, Ray S. Cline, has stated he "suspects" it to be genuine. According to Daniele Ganser, Licio Gelli, the Italian leader of the anti-Communist P2 freemason lodge bluntly told the BBC's Allan Francovich, "The CIA gave it to me".
Read more about this topic: US Army Field Manual 30-31B