Washington (CNN) A Jamaican man chose the wrong person to try to extort: the only one to lead both the FBI and CIA.

William Webster, who is now 94 years old, and his wife, Lynda, were targeted four years ago by a man who peddled a lottery scam over phone calls and emails. Over multiple phone calls, Keniel Aeon Thomas of Jamaica told the Websters he'd set their house ablaze or have a sniper shoot them in the back of the head if they didn't pay him thousands of dollars, according to prosecutors' filings.

The Websters say they used their knowledge of the FBI to help send him to prison, which a federal judge did on Friday after both spoke to the court.

"We are lucky that we have a few friends that could be helpful to us," Lynda Webster told the judge.

William Webster received the first call. The caller, Thomas, identified himself as "David Morgan," the head of "Mega Millions." Thomas told Webster he had won $15.5 million and a Mercedez-Benz and needed to wire $50,000 to cover taxes before collecting the award. That's when Webster first reached out to the FBI.

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