Harbury said her suspicions were further confirmed after a former guerrilla captive claimed to have seen Everardo alive in July 1992.

Santiago C. Lopez, a URNG member who served under Everardo, escaped after a year of imprisonment and reported seeing his former commander alive, Harbury said.

"Santiago was part of an experimental program from Argentina where some prisoners of war were selected for special treatment," she said. "[In this program], prisoners were tortured for five to six months to break them psychologically and told if they do not cooperate with the government their entire family will be killed."

Harbury said Santiago was able to escape because his family did not live in Guatemala.

Believing Everardo was being held in a clandestine torture center, Harbury collected letters of protest from members of Congress and human rights groups.

In September 1993 Harbury went on a hunger strike outside the Polytecnica, the Guatemalan equivalent of the Pentagon, to draw attention to Everardo's plight.

"I declared a seven day hunger strike and demanded a fair trial according to the Geneva Convention," she said. "Guatemalans came out in droves to support me with flowers and water."

In October 1994 she staged a second 32-day hunger strike that captured international media attention.

"I thought the peace accord would lead to Everardo's death at Christmas when the peace treaty went into effect," Harbury said. "I went on a hunger strike to the death and was repeatedly harassed by the Guatemalan government trying to get me to pass out so they could get me into a hospital."

On the 32nd day of her hunger strike, the American Embassy in Guatemala issued a demarche in which the U.S. government acknowledged Everardo was captured alive, Harbury said.

"My blood sugar levels were near coma levels and I had one eye closed because I couldn't open it," Harbury said, describing her condition when the demarche was issued.

Harbury then returned to Washington to push for sanctions against the Guatemalan government, but to no avail. During another hunger strike in Washington, D.C. in 1995, Rep. Robert G. Torricelli (D-N.J.) told Harbury that a Guatemalan General on the CIA's payroll ordered Everardo's execution.

Based on documents she obtained, Harbury said she thinks Everardo was tortured for one year, drugged by military doctors and kept in a full body cast to prevent his escape before he was murdered.

Towards the end of her talk, Harbury read from many U.S. government documents obtained under the Freedom of Information Act and discussed the legal implications of her case using hypothetical situations and rhetorical questions.

"What does national security mean and does it ever justify obstruction of justice and criminal activities," Harbury asked the audience. "Can U.S. officials knowingly and routinely get information extracted from murder and torture?...Can [the U.S.] aid and abet torture and can these decisions be made in Washington and still be constitutional?"

Harbury, who has filed civil rights suits against Guatemala, the CIA, the State Department and the National Security Council, said she still receives death threats. "Now they've gone hi-tech and send [threats] by e-mail."

The 90-minute discussion was sponsored by the David Rockefeller Center for Latin American Studies.

In the last half hour of the discussion, Harbury fielded questions from the audience on the relationship between the CIA and Harvard, and on U.S. interests in Guatemala.

Harbury's latest book, "Searching for Everardo: A story of love, war, and the CIA in Guatemala," is sold at bookstores in the square. Harbury donates proceeds from its sale to the Everardo Foundation, which she founded to help implement the 1996 Guatemalan Peace Accords