An indictment said Mariam Taha Thompson, 61, formerly of Rochester, Minnesota, was a contract linguist with a "top secret" security clearance who began working with US Special Forces in Erbil, Iraq in mid-December.

It said that one day after US airstrikes December 29 on installations of an Iraqi Shiite militia allied with Iran, Thompson began accessing US military computer files with the identities of US sources and information they had provided.

After Thompson was arrested on February 27, she admitted to investigators that she passed the information on the informants, together with a warning for a Hezbollah-linked target of US military intelligence, to a Lebanese national whom she had "a romantic interest in," according to the charges.

The Lebanese national is related to a Lebanese government official and "has apparent connections to Hezbollah," the Justice Department said in a statement.

"Thompson accessed dozens of files concerning human intelligence sources, including true names, personal identification data, background information, and photographs of the human assets, as well as operational cables detailing information the assets provided to the United States government," the Justice Department said.

Thompson was charged with transmitting national defense information to representatives of a foreign government -- Hezbollah of Lebanon -- the maximum penalty for which is life imprisonment.