A US government scientist was drugged by CIA agents and then thrown to his death from the 13th floor of a Manhattan hotel after he learned about secret torture sites in Europe, according to a lawsuit filed by his family.
The sons of Dr Frank Olson claim that their father was murdered in 1953 after he discovered that his biological research was being used to torture and kill suspects in Norway and West Germany.
After raising concerns about the killings, Dr Olson was allegedly given LSD in a glass of brandy and then executed by the CIA, triggering what his family claims is "a multi-decade cover-up that continues to this day".
The scientist began working with the spy agency in the 1950s and focused on biological weapons that could be transmitted through the air.
According to the lawsuit, filed Wednesday in Washington DC, he traveled to research sites in Norway, France and West Germany as well as Porton Down, a British government facility in Wiltshire.
During his travels in Europe he "witnessed extreme interrogations in which the CIA committed murder using biological agents that Dr Olson had developed".
The lawsuit gives no details about the reported deaths in Europe and the Ministry of Defence would not comment on Dr Olson's activities in Britain.
A MoD spokesman said that Porton Down had been used to develop countermeasures to biological weapons and "part of this work included ongoing collaboration with our international allies, including the US".
Dr Olson was apparently shaken by what he had seen and returned to the US resigned to resolve from the agency. On November 19, 1953 he was taken to a secret meeting Deep Creek Lake, Maryland, where he was given LSD hidden in a glass of brandy.
Days later he was brought to New York for "psychiatric treatment" by CIA officials who allegedly told his family that he had become unstable and violent.
At 2.30am on November 28, Dr Olson went through the window of the Statler Hotel's room 1018a, which he was allegedly sharing with a CIA doctor, and died in the street below.
The CIA initially claimed his death was an accident but in the 1970s, as its activities were investigated in the wake of the Watergate scandal, it admitted that he had been drugged and said that his death was a suicide.
Dr Olson's family was paid a settlement and invited to the White House by President Gerald Ford, who apologised for the government's concealment of the drugging.
However, the family remained unsatisfied with the government's account and in 1996 exhumed Dr Olson's body and claimed to have found evidence of a blow to the head suffered before his fall.
Prosecutors in New York re-opened an investigation and although they were unable to turn up new evidence decided to change Dr Olson's cause of death from "suicide" to "unknown".
The family are now suing the government, claiming that the CIA is continuing to conceal files relating to their father's death.
“The evidence shows that our father was killed in their custody. They have lied to us ever since, withholding documents and information, and changing their story when convenient," said Eric Olson.
A CIA spokeswoman said that its covert programmes of the 1950s had been "thoroughly investigated" and that "tens of thousands of pages related to the program have been declassified and released to the public.”
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