BISMARCK, North DaKota (AP) — Two more defendants have reached plea agreements with US prosecutors in a Jamaican lottery scam that authorities say bilked mostly elderly Americans out of millions of dollars.

Four of the 15 defendants have now reached such deals, including Lavrick Willocks, the man accused of being the kingpin.

Jason Jahalal and Xanu Morgan were among a group of eight suspects extradited from Jamaica to Bismarck, North Dakota, in April to face charges. All eight pleaded not guilty to conspiracy, fraud and money laundering charges and were scheduled for trial in January.

Jahalal and Morgan signed deals with prosecutors in late August under which they would plead guilty to one count of conspiracy, while the government agreed to drop 65 other counts of wire fraud, mail fraud and money laundering, court documents show.

The agreements are similar to those reached earlier by Alrick McLeod, who is scheduled to plead guilty October 16, and Willocks, who pleaded guilty in late July. His sentencing has not yet been scheduled.

Willocks faces up to 40 years in prison, though prosecutors have agreed to recommend only about 10 years because he cooperated with authorities.

Jamaican lottery scams have been happening for years, but prosecutors have said no cases of this magnitude have been prosecuted. The suspects are accused of calling victims about bogus lottery winnings, persuading them to send advance fees to receive the purported winnings, then keeping the money without paying out anything to the victims. Authorities say the alleged scam bilked at least 90 Americans out of more than US$5.7 million.

The investigation has been ongoing since a North Dakota woman lost her life savings of more than US$300,000 in 2011. It involves the FBI, the US Postal Inspection Service and the Justice Department’s Office of International Affairs.

Authorities have dubbed the case “Operation Hard Copy,” a reference to lists of prospective victims’ contact information used by scammers.

Of the suspects that have not reached plea deals, seven are still scheduled for trial in January, two are in Jamaica awaiting extradition and two others remain fugitives.