WASHINGTON -- A Pentagon intelligence analyst who attended war games conducted by the U.S. Atlantic Command in 1996 was charged Friday with spying for Cuba.

Ana Belen Montes, an employee of the Defense Intelligence Agency, transmitted a substantial amount of classified information to the Cuban intelligence service, an FBI affidavit alleged.

Montes appeared before a U.S. magistrate in Washington and was charged with conspiracy to deliver U.S. national defense information to Cuba. She entered no plea and was ordered held without bond.

Montes has worked for the DIA, the intelligence arm of the Defense Department, since 1985, authorities said.

In a 17-page affidavit, the FBI alleged that earlier this year Montes contacted the Cuban intelligence service via shortwave radio.

The FBI secretly entered Montes' residence under a court order May 25 and uncovered information about several Defense Department issues, including a 1996 war games exercise conducted by the U.S. Atlantic Command.

According to the affidavit, the DIA said that Montes attended the war games exercise in Norfolk, Va., as part of her official duties at DIA. The FBI said it found information on the hard drive of her laptop computer.

One partially recovered message deals with "a particular special access program related to the national defense of the United States," which is so sensitive that it could not be publicly revealed in the court documents, the document said.

Disclosed agent's arrival

According to the FBI's affidavit, some of the messages suggested that Montes disclosed the upcoming arrival of a U.S. military intelligence officer in Cuba.

"As a result," the FBI said, "the Cuban government was able to direct its counterintelligence resources against the U.S. officer."

The FBI said Montes got a message back from her Cuban handlers stating, "We were waiting here for him with open arms."

One message found on the hard drive was from her Cuban intelligence service handler said that she had provided "tremendously useful ... information."

Another message from her Cuban contact said in regard to the 1996 war games exercise: "Practically everything that takes place there will be of intelligence value. Let's see if it deals with contingency plans and specific targets in Cuba."

The FBI said they had Montes under surveillance since May.