Transcript for Former Air Force counterintelligence specialist charged with spying

former air force intelligence specialist, who defected to Iran against the U.S. Now, she's been charged espionage. Monica Witt worked for the air force and then as a contract. She's now tonight accused of betraying the U.S. And her former colleagues. Did she reveal missions, did she reveal officers' names? Here's ABC's chief global affairs correspondent Martha Raddatz tonight. Reporter: It is an extraordinary espionage indictment. Monica Witt, a former air force counterintelligence specialist, not only charged with spying, but defecting to Iran. The Texas native accused of revealing highly classified Pentagon programs, that the FBI said today "Could cause serious damage to national security." In addition, according to the indictment, Witt identified former colleagues to Iranian intelligence. She blew the cover of her counterintelligence colleagues and put them in mortal danger. Reporter: The FBI said her motive was "Ideological," texting a contact, saying, "I am endeavoring to put the training I received to good use instead of evil." Later texting that, "I just may go public with a program and do like Snowden." A smiley face at the end. Let's get to Martha Raddatz, with us live tonight. And Martha, you have learned that the FBI warned Witt that the Iranians might try to recruit her during her trips to Iran? Reporter: They had, David, and she said she told them she would refuse to provide information about her work. A statement that the FBI now says was a lie, but of course, it will be nearly impossible to try this case, David, since she remains in Iran. David? Martha Raddatz tonight. Martha, thank you.

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