The FBI is offering a $200,000 reward for help capturing a former U.S. Air Force counterintelligence specialist who defected to Iran in 2013. 

A federal grand jury indicted Monica Elfriede Witt, 47, on charges of espionage, including transmitting national defense information to the government of Iran, according to the FBI. 

"Witt allegedly betrayed her oath to the Constitution more than a decade ago by defecting to Iran and providing the Iranian regime National Defense Information and likely continues to support their nefarious activities," Daniel Wierzbicki, special agent in charge of the FBI Washington Field Office’s Counterintelligence and Cyber Division, said Thursday in announcing the reward. 

"The FBI has not forgotten and believes that during this critical moment in Iran’s history, there is someone who knows something about her whereabouts. The FBI wants to hear from you so you can help us apprehend Witt and bring her to justice." 

Witt was a U.S. Air Force intelligence specialist for the U.S. military branch's Special Investigations division.

She served from 1997 to 2008 before working as a U.S. government contractor until 2010. Her military service and contracting employment provided her access to SECRET and TOP SECRET information relating to foreign intelligence and counterintelligence, including the true names of U.S. Intelligence Community undercover personnel, the FBI says.

The agent also alleges Witt’s defection to Iran has benefited the Islamic Revolutionary Guard Corps, which has elements responsible for intelligence collection, unconventional warfare, and providing direct support to multiple terrorist organizations targeting U.S. citizens and interests.