The British Naval Attaché at the Oslo Legation, Rear-Admiral H Boyes, received an anonymous package at the beginning of November 1939 detailing German secret weapons development. The document contained information on such things as radar development, remote controlled gliders, acoustically and magnetically detonated torpedoes, and long-distance air navigation techniques with suggested countermeasures. The report also revealed Peenemünde and Rechlin as Wehrmacht experimental weapons test sites.
Three copies of the Oslo report with drawings and English translation were forwarded to the Director of Naval Intelligence on 6 November 1939.
After the war it was established that the report had been supplied by German mathematician and physicist Hans Mayer.
The first part of the report is reproduced below and includes copies of the drawings.