Germany's most notorious postwar neo-Nazi party was led by an intelligence agent working for the British, according to both published and unpublished German sources.
The alleged agent - the late Adolf von Thadden - came closer than anyone to giving the far-right real influence over postwar German politics.
Under his leadership, the National Democratic party (NPD) made a string of impressive showings in regional elections in the late 60s, and there were widespread fears that it would gain representation in the federal parliament.
Yet, according to a report earlier this year in the Cologne daily, the Kölner Stadt-Anzeiger, the man dubbed "the New Führer" was working for British intelligence throughout the four years he led the NPD, from 1967 to 1971.
However, a former senior officer in German intelligence told the Guardian this week that he had been informed of a much longer-standing link between Von Thadden and British intelligence. His recollection raises the question of whether the German far-right-winger was under the sway of M16 when he and others founded the NPD in 1964.