Seventeen people have been charged in the US with the theft of $42m of Holocaust compensation funds provided by the German government.
Prosecutors alleged the 17 fooled a non-profit-making group that distributes the funds into making 5,500 false payments.
Six of those charged work for the group - the Conference on Jewish Material Claims Against Germany.
The chairman of the group said it was "outraged" at the alleged thefts.
It had detected the matter itself and contacted the FBI.
If convicted, the defendants could face up to 20 years in jail.
The Conference on Jewish Material Claims Against Germany was founded in 1951 and has helped distribute two types of compensation - a $3,600 one-off payout to refugees who were victims of Nazi persecution and a monthly payment of $411 to Nazi victims who live on less than $16,000 a year.
The indictment in New York alleges that between 2000 and 2009 the six employees approved claims for people who should not have qualified for compensation and then shared the payout with the other defendants.
Chairman of the claims conference, Julius Berman, said: "We are outraged that individuals would steal money intended for survivors of history's worst crime to enrich themselves."
US Attorney Preet Bharara said: "If ever there was a cause that you would hope and expect would be immune from base greed and criminal fraud, it would be the claims conference, which every day assists thousands of poor and elderly victims of Nazi persecution.
"Sadly, those victim funds were themselves victimised."
FBI assistant director Janice Fedarcyk said: "This was a brazen miscarriage of the compensation programmes."
The indictment said some of the claims were made by people born after World War II. One claimant was not Jewish.