Former national security adviser Michael Flynn's onetime business partner and another associate were charged in an illegal lobbying effort aimed at winning Turkey's extradition of a cleric living in the USA.

Bijan Rafiekian, who served as a director and vice chairman of Flynn Intel Group, appeared in a Virginia federal court Monday where he was accused of failing to register as an agent for Turkey. Kamil Alptekin, a Turkish-Dutch citizen living in Instanbul, also was charged in the scheme in which he allegedly served as a secret conduit for the Turkish government.

The case, which alleges that Rafiekian and Alptekin sought to conceal the Turkish government's role in the effort to extradite Fethullah Gulen, was brought by federal prosecutors in Virginia, not Russia special counsel Robert Mueller.

Gulen, living in Pennsylvania, was accused by Turkey in 2016 in a failed coup attempt, prompting the government to seek the cleric's return from exile in the USA.

Flynn, who was not specifically named in the court documents Monday, is set to be sentenced Tuesday by Mueller's team in a separate case in which the retired three-star Army general pleaded guilty to lying to the FBI related to his communication with Russian Ambassador Sergey Kislyak.

Mueller's team recommended that Flynn serve no prison time because of his substantial cooperation in the Russia inquiry and his assistance in two other inquiries, probably including the case against Rafiekian and Alptekin.

Although Flynn was not charged in the Virginia case, he and his company were central to the Gulen extradition scheme, which was secretly funded by the Turkish government and involved payments totaling $600,000 to Flynn's company, prosecutors alleged.

Among their efforts to advance the project, according to court documents, Flynn, Rafiekian and Alptekin attended a meeting with two Turkish government officials Sept. 19, 2016, to discuss the project and "efforts to convince the U.S. government to extradite (Gulen) to Turkey."

Throughout the 21-page charging document, Flynn is referred to as "Person A."

Prosecutors asserted that Alptekin disguised the Turkish government's role in the project by posing as Flynn's client and operator of a Dutch company through which payments from Turkey were funneled to the Virginia company headed by Flynn.

Under the alleged agreement, Alptekin's company in the Netherlands was to receive 20 percent in kickbacks from Flynn's company.

Rafiekian is charged with conspiracy in addition to serving as an undeclared agent of the government of Turkey. If convicted, he could face a maximum prison term of 15 years.

Alptekin is charged with conspiracy, illegal lobbying for Turkey and four counts of making false statements to the FBI.

If convicted on all charges, he could face a maximum penalty of 20 years in prison.

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