BUENOS AIRES — Former Gen. Luciano Benjamín Menéndez, one of the most notorious oppressors during Argentina’s era of brutal dictatorship, from 1976 to 1983, died on Tuesday in the central city of Córdoba. He was 90.
Alejandro Richetta, the medical director at Córdoba Military Hospital, where Mr. Menéndez died, said the cause was complications of bile duct cancer.
Mr. Menéndez had been under house arrest since 2012 because of his health problems. He had received 14 life sentences — the most of any military leader from that era — for crimes that included homicide, torture, forced disappearances and the kidnapping of a newborn.
Overall, Mr. Menéndez was sentenced 16 times, indicted in 49 cases and under investigation in 25 more for crimes against humanity.
Human rights groups say that some 30,000 people were killed or forcibly “disappeared” under the military junta that ran the country in those years. Roughly 500 newborns were believed to have been kidnapped from political prisoners.
Mr. Menéndez, as head of the Third Army Corps from 1975 to 1979, was in charge of what the junta called anti-subversive actions in 10 Argentine provinces. He never expressed regret for his actions. The use of force, he said, was necessary to combat “Marxist” forces.
“The proceedings employed in the fight against the subversion are being criticized,” he said in a 1984 interview, “but those proceedings must be judged from the optic of an unconventional war.”
He was born into a military family on June 19, 1927, in San Martín, Buenos Aires Province. Both his father and grandfather were officers. An uncle, Benjamín Menéndez, also a military officer, attempted to overthrow President Juan Domingo Perón in 1951. A cousin, Mario Benjamín Menéndez, would become military governor of the Falkland Islands (known locally as the Islas Malvinas) during Argentina’s ill-fated occupation of them in 1982.
Luciano Menéndez rose quickly through the ranks and at 45 became one of the youngest officers to be promoted to general in Argentina.
“His file was filled with nothing but praise,” said Camilo Ratti, a Córdoba journalist who wrote a biography of Mr. Menéndez.
As part of his military training, Mr. Menéndez spent a year in Fort Lee, Va., and later studied anti-insurgency tactics under the tutelage of French military officials, who held the view that the “enemy was not external but rather within society,” Mr. Ratti said.
Mr. Menéndez was in charge of one of the largest illegal detention centers in the country, known as La Perla, where thousands were detained, and he participated directly in the torture and murder of political prisoners. He forced all those under his command to participate in torture and homicides in what became known as a “blood pact.”
“Everybody who was under him had to get their hands dirty so no one could claim ignorance about what was happening,” said Carlos Gonella, the lead prosecutor in three trials against Mr. Menéndez. “He died, and that pact never broke.”
Mr. Menéndez was considered a hawk within the military leadership. He was known to confront junta leaders when, in the face of international criticism, they pushed generals to tone down the antisubversive campaigns. He deemed the junta leaders too soft.
His disagreements with the military leadership led him to mount an insurrection in late 1979, but it was quickly crushed. He was imprisoned for 90 days and forced into retirement.
Mr. Menéndez’s anger at anyone who questioned him was immortalized in a 1984 photograph that showed aides restraining him as he brandished a knife at protesters who were yelling “Coward!” and “Murderer!” as he exited a television studio.
“He became a symbol of the dictatorship, but there were many others like him,” said Paula Canelo, a sociology professor at Buenos Aires University and the author of books on military history. “He was not some lone crazy man, but rather someone who was a product of the era in which the state transformed itself into a criminal agency.”
The junta stepped down in 1983 amid domestic and international pressure after its attempt to seize the Falkland Islands from Britain ended in embarrassing defeat. In elections called by the junta, Ricardo Alfonsín was chosen president, and the country has been under democratic rule ever since.
Former President Carlos Menem granted Mr. Menéndez a pardon in 1990, but it was declared unconstitutional in 2005. Mr. Menéndez received his first life sentence in 2008, at a time when there was a surge in trials against dictatorship-era leaders.
The Defense Ministry stripped Mr. Menéndez of his military rank in 2011.
His wife, Edith Angélica Abarca, died in 2012. He is survived by five their seven children.