Some 75% (105,000 out of 140,000) of the Jewish population perished in the Holocaust, most of whom were murdered in Nazi death camps.[3] A number of resistance groups specialized in saving Jewish children, including the Utrechts Kindercomité [nl], Landelijke Organisatie voor Hulp aan Onderduikers [nl], Naamloze Vennootschap (NV), and Amsterdam Student Group.[4] The Columbia Guide to the Holocaust estimates that 215–500 Dutch Romanis were killed by the Nazis, with the higher figure estimated as almost the entire pre-war population of Dutch Romanis.[5]