Our guide stopped at this plaque on a bank & explained that it was there to commerate the Jews that were captured in the Netherlands during WW II because numerous Nazi friendly Dutch officials would give up their Jewish countrymen to the Nazis who then paid the traitors with the captured Jews’ belongings & money. Further reseach turned up the Henneicke Column, a formal group of Dutch Nazi collaborators formed for this purpose. There is a book about t his group: "A Price on Their Heads, Kopgeld, Dutch bounty hunters in search of Jews"