(CNN) Two people have pleaded guilty to conspiracy to commit mail fraud for their roles in one of the biggest consumer scams in history, according to court documents unsealed this week.

Canadian citizens Maria Thanos and Philip Lett managed the day-to-day operations of Infogest Direct Marketing, according to the documents. Previous government filings show that this Canadian company used letters allegedly written by French clairvoyant Maria Duval to prey on the sick and elderly. Infogest ran the North American arm of the scam, raking in more than $200 million from more than 1.4 million victims in the United States and Canada.

Their alleged boss, who the government says was the leader of Infogest, has also been charged. Patrice Runner faces 18 counts of mail and wire fraud and conspiracy to commit mail fraud, wire fraud and money laundering. Court records show that Runner's arrest warrant was provided to both Interpol and authorities in Spain, where the Department of Justice says he was arrested in December. Social media suggests he lives in Ibiza, Spain, and the Spanish government is now considering an extradition request by the United States, according to the DOJ.

It is unclear whether Runner has entered a plea, and he has not yet had a US court appearance. His attorney says Runner "is contesting the validity of any criminal accusation that might be held against him by any authority whatsoever."

Read about the psychic and the scam After two years investigating one of history's longest-running frauds, CNN's Blake Ellis and Melanie Hicken finally met its central figure: psychic Maria Duval. What did she have to say?

The criminal charges are the first brought by the US government against any of the scam's key players. Many other perpetrators -- including some of the original masterminds -- remain at large around the world.

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