Augusto Pinochet, the ex military dictator of Chile, directly ordered a car bombing on US soil that killed a former Chilean diplomat and a US citizen in September 1976, according to recently declassified documents.
"The CIA concludes that its review provides 'what we regard as convincing evidence that President Pinochet personally ordered his intelligence chief to carry out the murders'," said a recently released memo sent to US President Ronald Reagan in 1987.
"It also confirms that 'Pinochet decided to stonewall on the US investigation to hide his involvement' and continues to do so, including by considering 'even the elimination of his former intelligence chief'," the memo said.
The 1,000 pages of declassified documents were personally delivered to Chilean President Michelle Bachelet by US Secretary of State John Kerry during a visit this week.
On September 21, 1976, the ex Chilean foreign minister Orlando Letelier and a US colleague named Ronni Karpen Moffitt died when a bomb exploded in their vehicle as they rode on Massachusetts Avenue in Washington DC. Moffitt's husband survived the attack.
Secret agents in Pinochet's regime were accused of carrying out the bombing, but the ex dictator was never directly linked to the attack.
At the time, Letelier was in exile in the US after serving in several key posts in the government of former President Salvador Allende, the socialist who was popularly elected in 1970 but was ousted and died in a bloody US-backed coup in 1973.
Letelier was working at the Institute for Policy Studies and was lobbying the United States to back away from supporting Pinochet, who was accused of carrying out thousands of kidnappings and executions of dissidents until his rule ended in 1990.
In the documents, first published by the National Security Archive at George Washington University, the former US Secretary of State George P. Schultz wrote Reagan amid an effort to convince him to cut ties with Pinochet.
In the 1987 memo, Schultz described the bombing as "the only clear case of state-supported terrorism that has occurred in Washington DC."
"It is not clear whether we can or would want to consider indicting Pinochet, even if we had more public sources of evidence," Schultz went on. "Nevertheless, this is a blatant example of a chief of state's direct involvement in an act of state terrorism, one that is particularly disturbing both because it occurred in our capital and since his government is generally considered to be friendly."
In another document declassified this week, US officials in 1987 told one another that Manuel Contreras, the former chief of the Chilean spy agency known as DINA, "admitted that he ordered the assassination, but claimed direct orders from Pinochet."
Pinochet lost a democratic referendum in 1988 and left the presidency of Chile in 1990. The general died in 2006 before ever fully confronting punishment for abuses during his rule. Contreras died in August of this year in a military prison while serving a 520-year sentence for crimes against humanity.
Contreras and an ex-general, Pedro Espinoza, were convicted of charges in Chile related to the 1976 attack. This week, Fabiola Letelier, Orlando Letelier's sister, said she will request that the case be reopened and that other possible culprits be investigated.
"We've never doubted it was him [Pinochet] who gave the order," Fabiola Letelier told the news site Emol.
Bachelet's administration made no formal response to the US documents.
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