Denunciations of Jews to German authorities came from a variety of different sources, sometimes even from their "protectors." In 1944, Eva and Liane Münzer (pictured here) were reported to the police as a result of a domestic fight between their rescuers. The irate husband denounced his wife and the two Jewish girls. The Münzer sisters were sent to Auschwitz and killed.
Alfred Munzer; US Holocaust Memorial Museum