Britain's Security Service, known as MI5, worked with the Boy Scout movement to help it avoid infiltration by both communists and fascists between the world wars, previously secret papers show.
The files were published online for the first time Thursday by the National Archives in London as part of its commemorations of World War I, which began 100 years ago.
They also include a transcript of an interrogation of the Dutch-born German spy Mata Hari and reports on Arthur Ransome, author of the "Swallows and Amazons" children's books, and labeled "an ardent Bolshevist."
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