Nacht und Nebel
Reinhard Heydrich's "Sicherheitsdienst" (Security Service; SD) was given responsibility for over-seeing and carrying out the "Nacht und Nebel" decree. The SD was mainly an information-gathering agency, while the Gestapo was the main executive agency of the political police system. The decree was meant to intimidate local populations into submission, by denying friends and families of seized persons any knowledge of their whereabouts or their fate. The prisoners were secretly transported to Germany, and vanished without a trace. In 1945, abandoned SD records were found to include merely names and the initials "NN" ("Nacht und Nebel"); even the sites of graves were unrecorded. The Nazis even coined a new term for those who "vanished" in accordance with this decree; they were "vernebelt"—"transformed into mist". To this day, it is not known how many people disappeared as a result of this decree. The International Military Tribunal at Nuremberg held that the disappearances committed as part of the "Nacht und Nebel" program were war crimes which violated both the Hague Conventions and customary international law.