"It is a sad day for America when one of its citizens betrays our country", said Demers.
USA authorities on Wednesday charged former Air Force intelligence officer Monica Witt with helping Iran launch a cyber-spying operation that targeted her former colleagues after she defected from the United States.
Witt served in the US Air Force from 1997 to 2008, becoming a special agent in the Air Force Office of Special Investigations, its counterintelligence unit.
Monica Witt allegedly turned over classified information about USA intelligence officers after defecting to Iran in 2013, according to a newly unsealed indictment.
The government issued an arrest warrant for Witt, who remains at large.
After leaving the Air Force, she worked as a defense and intelligence contractor, but by 2012 her politics had begun to turn.
Tabb said investigators believe Witt's motive was "ideological", and the indictment against her alleges that, before she defected, she appeared in videos that she knew would be broadcast by Iranian media outlets and "made statements that were critical of the United States government".More news: Scanning Younger Women Could Prevent Breast Cancer
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"She chose to turn against the United States and shift her loyalty to Iran", said Jay Tabb, the FBI's executive assistant director for national security. She also gave Iranians the code name and classified mission of a special U.S. Department of Defense operation. According to authorities, she started working on behalf of Tehran by disclosing classified information and compiling research on US intelligence personnel she previously worked with.
The four Iranians were acting on behalf of the government-linked Iranian Revolutionary Guard, prosecutors said. During her USA government career, authorities said Witt was granted high-level security clearances and was posted overseas on several occasions for counterintelligence missions.
But later that year, she helped an unnamed Iranian-American official produce an anti-American propaganda film. For me? Well, I loved the work, and I am endeavoring to put the training I received to good use instead of evil.
Jay Tabb, the FBI's executive assistant director for national security, said investigators believe Witt shared information that "could cause serious damage to national security", though he declined to provide specific details of the operations she allegedly disclosed.
The indictment also alleges that Witt planned to go to Russian Federation in 2013 to contact WikiLeaks without disclosing her location.
During that time, she was granted high-level security clearances, learned Farsi at a US military language school, and was deployed overseas for counterintelligence missions in the Middle East.
Mesri, Masampour and Parvar also face sanctions for their involvement with Net Peygard, according to the U.S. Treasury Department.