Recently declassified US intelligence documents have revealed brutal methods employed by Argentina's former military junta during its 1976-1983 "dirty war" against dissidents.
The archive shows that on August 20 1976, agents of Argentina's dictatorship dynamited the bodies of 30 people who had been detained as dissidents in a blast that spread their remains over a wide radius.
The grisly details of the explosion that tore apart the bodies of 10 women and 20 men who were executed in the Argentine city of Pilar were found in a US Central Intelligence Agency (CIA) report posted by the independent US National Security Archive.
Thousands of people were tortured, killed and forcibly disappeared in a government-sponsored crackdown on leftist dissidents during the "dirty war".
The report said 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 that the leader of Argentina's military junta, Gen Rafael Videla, was "annoyed that the bodies were left so prominently displayed".
Gen Videla wanted them dead, the report said. He was just annoyed that it had been 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 former American 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.
Then-US assistant secretary of state for human rights Patricia Derian wrote in a 1979 summary: "We continue to receive numerous highly credible reports that torture is used routinely in the interrogation of detainees.
"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).
"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. The baby thefts set Argentina's dictatorship apart from all the other juntas that ruled at the time in South America.
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," Ms Derian reported.
Carlos Osorio, who directs the National Security Archive's Southern Cone Documentation Project, said: "The narratives by US intelligence agencies on what I call the military killing machine throw shivers through your back.
"There are precise details by the CIA on how the machine worked and was organised.
"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."