The United States has deported a former Argentine army officer accused of being chief interrogator at a torture center operated by the past military dictatorship, U.S. authorities said Tuesday.

U.S. immigration officials escorted former Maj. Ernesto Guillermo Barreiro on a commercial flight and handed him over to Interpol representatives here Tuesday, the U.S. Embassy said.

Prosecutors say Barreiro was chief interrogator at the feared "La Perla" torture camp in central Argentina from 1976 to 1979, the brutal early years of a military dictatorship that lasted until 1983.

Argentine authorities say they believe Barreiro went to the United States in 2004, soon after an Argentine federal judge called for his detention along with 10 others in connection with the torture and death of a 17-year-old student, Diego Hunziker, who was kidnapped in 1977.

He was briefly detained in 1987 on six charges of torture and one of torture leading to death, but was later released, according to court documents.

Barreiro was arrested in The Plains, Virginia, in April and was later convicted of fraudulently obtaining a U.S. visa by denying he had ever faced criminal charges. He was deported after serving his sentence.

Scores of military officers found shelter from prosecution under Argentina's 1980s amnesty laws, but the Supreme Court in 2005 struck down those laws and many suspected rights violators are now being hauled back into court.

Nearly 13,000 people are officially reported as missing during Argentina's dictatorship — most believed to have been kidnapped and killed, often after torture. Human rights groups say the toll approaches 30,000.

U.S. immigration authorities say he was caught by a special unit created to track alleged human rights violators from foreign nations has identified more than 800 cases from 85 countries, with people returned to Haiti, Somalia, Ethiopia, El Salvador, Honduras and Bosnia.