Germany's domestic intelligence service, a postwar creation known as the Federal Office for the Protection of the Constitution, or Verfassungsschutz, is broadly comparable to the intelligence wing of the U.S. Federal Bureau of Investigation.

WSJ: German Intelligence Chief to Step Down

The Federal Office for the Protection of the Constitution, the domestic intelligence service, thinks 25, 000 people belong to far-right groups, of whom 9, 500 could be violent.

ECONOMIST: Neo-Nazi crimes in Germany: A horror from the past | The

It is understood the Federal Bureau of Intelligence (FBI), the Central Intelligence Agency (CIA) and the Office of Naval Intelligence all had dossiers on Oswald prior to the shooting following his defection from Russia to America in 1961.

BBC: 28 September