(CNN) Rep. Mark Sanford, the South Carolina Republican and frequent critic of President Donald Trump, had his own run-in with accused Russian spy Maria Butina at his family farm last year.

Butina and her boyfriend, Paul Erickson, were two of roughly 300 guests attending a post-Thanksgiving barbeque last year that Sanford holds annually at his farm roughly an hour outside of Charleston, South Carolina.

Butina was charged this week with acting as a covert Russian agent in the US, conspiring with a Russian official and allegedly using sex and deception to build her network and expand her influence. Her efforts, according to prosecutors, were aided by an American political operative who helped her gain access to US political organizations and politicians. That person is not identified in court filings but the activities and description match Erickson, who has been involved in a years-long romantic relationship with Butina. Erickson has not faced charges in relation to Butina's case.

Rep. Mark Sanford, at left, a South Carolina Republican, and Maria Butina, an accused Russian spy appears at right.

But to Sanford, Butina was the girlfriend of his business-school classmate who was trying to start the equivalent of the National Rifle Association in Russia.

"I did meet her, a few interactions were pleasant," Sanford told CNN in an interview. "It's the girlfriend of a guy I've known for 30 years. She seemed nice enough."

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