Maria Butina, the 30-year-old Russian national who admitted to secretly working for the Kremlin to infiltrate political groups in the U.S., was sentenced to 18 months in prison Friday. Butina has been jailed since last July on charges of conspiracy and acting as a foreign agent.

The second charge against Butina was dismissed as part of her plea agreement in which she chose to cooperate with the government. She will be credited with time served.

Prosecutors believe that Butina violated U.S. espionage laws by infiltrating political organizations, including the National Rifle Association, on behalf of the Kremlin. Butina worked with Deputy Governor of the Central Bank of Russia Aleksandr Torshin and was allegedly laying the groundwork for a backchannel between Russians and a handful of prominent U.S. conservatives.

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"Her backchannel communications had serious potential harms," Assistant U.S. Attorney Erik Kenerson said on Friday. Kenerson said Butina spent "significant time" working to build such a backchannel, hosting "friendship dinners," organizing a delegation for the national prayer breakfast, and meeting with contacts. Many of her contacts allegedly came from Paul Erickson, a South Dakota Republican operative who later dated Butina. Erickson was charged in a related fraud scheme in February and has since pleaded not guilty. His case is pending.

Butina's attorney, Alfred Carry, claimed that his client was honest in his dealings with her. Her legal team pushed for Butina's sentence to be between zero and six months. Addressing the court prior to her sentencing, Butina reaffirmed her cooperation with the U.S. government and said she was unaware she needed to register under the Foreign Agents Registration Act.

Her voice cracking at times, Butina strongly expressed her remorse and desire to return home to be with her family. "I have three degrees, but now I'm a convicted felon," she said, adding "instead of building peace, I created discord."

District of Columbia Judge Tanya Chutkan seemed receptive to Butina's comments, describing them as sincere. However, when it came to actual sentencing, Chutkan took a harsher tone. "This was no simple misunderstanding by an overeager foreign student," she said.

As conspiracy to act as an agent of a foreign government is a felony offense, Butina will be deported following her release. She will be unable to petition to return to the U.S. for 10 years.

Clare Hymes and Rob Legare contributed reporting.