Agents operating for Argentina's 1976-1983 dictatorship on August 20, 1976, dynamited the bodies of 30 people who had been detained as dissidents, in a blast that spread their remains over a wide radius.
The horrific details about the explosion that tore apart the bodies of 10 women and 20 men executed in the city of Pilar were found in a recently declassified Central Intelligence Agency report posted Thursday by the independent National Security Archive.
Thousands were tortured, killed and forcibly disappeared in a government-sponsored crackdown on leftist dissidents during the dark days Argentina's 1976-1983 military dictatorship The report says the 1976 blast was meant "to send a bloody message to other alleged militants to cease their activities five months after the military coup."
Sources told the CIA the leader of the military junta, General Rafael Videla, was "annoyed that the bodies were left so prominently displayed."
Videla wanted them dead, it said. He was just annoyed that it was done so blatantly.
The documents are a small selection of The Argentina Declassification Project, the largest government-to-government declassification effort in US history authorised by President Barack Obama. The project was completed with a final transfer last month. The records describe in detail "brutal methods" used by Argentina's military.
"We continue to receive numerous highly credible reports that torture is used routinely in the interrogation of detainees," then-US Assistant Secretary of State for Human Rights Patricia Derian told the Secretary of State in a 1979 summary.
"The electric 'picana,' something like a supercharged cattle prod, is still apparently a favourite tool, as is the 'submarine' treatment (immersion of the head in a tub of water, urine, excrement, blood, or a combination of these)," Derian said in her report. "There is no longer any doubt that Argentina has the worst human rights record in South America."
Human rights groups estimate about 30,000 people were killed or forcibly disappeared during Argentina's dictatorship. Some were pregnant women who were "disappeared" right after giving birth in clandestine torture centres.
Women were also the target of sexual violence. Others were tortured with live rats or had not been exposed to the sun for so long that "their skin colour is greenish," Derian reported.
"The narratives by US intelligence agencies on what I call the military killing machine, throw shivers through your back," Carlos Osorio, who directs the National Security Archive's Southern Cone Documentation Project, told The Associated Press.
"There are precise details by the CIA on how the machine worked and was organised," he said. "The documents we have identified shed light in the case of dozens of victims, the units the perpetrators belonged to and the circumstances of the crimes committed by the junta."