WASHINGTON – Federal prosecutors revealed charges on Wednesday that a former Air Force intelligence officer had revealed defense secrets and the identity of at least one U.S. intelligence officer to the Iranian government.

Monica E. Witt was named in an indictment unsealed Wednesday, which also charged four Iranian nationals who prosecutors alleged were involved in cyber operations against her former U.S. military colleagues. Witt is charged with espionage, conspiracy and other crimes.

Federal authorities said that Witt defected to Iran in 2013, and allegedly provided the government with sensitive defense information and the identity of at least one U.S. intelligence officer. Before boarding her flight to Tehran, prosecutors said, she typed an email to an associate saying: "I'm signing off and heading out! Coming home." She closed with a smile emoji.

Assistant Attorney General John Demers, chief of the Justice Department's National Security Division, said Witt's alleged activities violated "her solemn oath to protect and defend our country, and the bounds of human decency."

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"This case underscores the dangers to our intelligence professionals and the lengths our adversaries will go to identify them, expose them, target them, and, in a few rare cases, ultimately turn them against the nation they swore to protect," Demers said.

Before traveling to Iran in 2012, federal authorities said Witt was warned that she was at risk of potential recruitment by Iranian intelligence officials, but she elected to continue with her travel plans.

Witt served as a Air Force military intelligence specialist for more than 10 years before leaving in 2008 to begin work as a defense contractor.

She left that post in 2010, and then began excursions to Iran where authorities believe she remains.

This article originally appeared on USA TODAY: Former Air Force intelligence officer charged with spying for Iran and revealing defense secrets