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The Police Regiment North (Polizei-Regiment Nord) was a police formation under the command of the SS of Nazi Germany. During Operation Barbarossa, it was deployed in German-occupied areas of the Soviet Union, in the Army Group North Rear Area.
Alongside the Einsatzgruppen detachments, it perpetrated mass murder in the Holocaust. The information on the scope of the unit's activities remains limited as, in contrast to the Police Regiment Centre and South, the 1941 reports of the unit were not intercepted by the British intelligence. Prützmann's command experienced communications difficulties during the summer of 1941. Then starting on September 12, the HSS-PF were instructed to not transmit their reports over the radio. Thus, none of its reports were decrypted as part of the operation Ultra, the British signals intelligence program.
Smith, Michael (2004). "Bletchley Park and the Holocaust". In Scott, L. V.; Jackson, P. D. (eds.). Understanding Intelligence in the Twenty-First Century: Journeys in Shadows. Routledge. ISBN0714655333.