U.S. prosecutors say the sentence for a man convicted in North Dakota of leading a Jamaican lottery scam should reflect the "severe mental anguish" he caused his victims.

Authorities say Sanjay Williams, of Montego Bay, Jamaica, was a "lead broker" who bought and sold "sucker lists" of potential victims. He was found guilty during a two-week trial in May of conspiracy, wire fraud and money laundering.

A sentencing memorandum filed Wednesday by the U.S. government notes that one witness testified that Williams threatened to rape her daughters and kill her son, and at least one victim committed suicide "after suffering greatly."

"The crime has a great negative impact on the people of Jamaica, as well, who are also victimized through increased lawlessness, including murder," Assistant U.S. Attorney Clare Hochhalter wrote.

Charlie Stock, who was Williams' attorney during trial, did not immediately respond to a request seeking comment on prosecutors' suggestion sentence. Williams has replaced other lawyers during the case and has written numerous letters to the judge complaining about his treatment.

Jamaican lottery scams have been happening for years, but few cases of this magnitude have been prosecuted. The case began when an FBI agent from North Dakota interviewed a Harvey woman who said she was scammed out of $300,000 after someone called and told her she had won $19 million and a new car, and needed only to pay taxes and fees. The investigation led authorities to a married couple from South Dakota who had been scammed and to others around the country.

Williams faces a maximum sentence of 40 years in prison. Sentencing is scheduled for Oct. 5 in Bismarck.