A Nazi hunter is a private individual who tracks down and gathers information on alleged former Nazis, SS members and Nazi collaborators involved in the Holocaust, typically for use at trial on charges of war crimes and crimes against humanity. Prominent Nazi hunters include Simon Wiesenthal, Tuviah Friedman, Serge and Beate Klarsfeld, Ian Sayer, Yaron Svoray, Elliot Welles, and Efraim Zuroff.