The United States relied on the assistance of dozens of German scientists to develop invasive interrogation techniques targeting the Soviet Union in the early years of the Cold War, according to a new book on the subject. The book, entitled Operation Paperclip: The Secret Intelligence Program that Brought Nazi Scientists to America, by American journalist Annie Jacobsen, is to be published this week.

Operation PAPERCLIP was initially set up during World War II by the US Office of Strategic Services (OSS), a forerunner of the Central Intelligence Agency (CIA). Its aim was to recruit scientists that had previously been employed by the German Third Reich, with the primary goal of denying German scientific expertise to the USSR. Hundreds of former Nazi scientists were brought to the US under secret military research contracts during the second half of the 1940s. Eventually, the recruited scientists were used to augment an entire array of American government-sponsored endeavors, including the space program and several intelligence collection techniques.

Jacobsen’s book details Operation BLUEBIRD, a program run by the CIA under PAPERCLIP, which employed former Nazi biological weapons experts, chemists and medical doctors. The latter were tasked with employing lysergic acid diethylamide, commonly known as LSD, in order to involuntary extort confessions from Soviet intelligence targets. In several cases, the hallucination-inducing chemical substance was dispensed on Soviet captives, who were also subjected to hypnosis and other methods of psychological manipulation.

According to the book, the techniques were developed under the primary supervision of Dr. Walter Schreiber, Germany’s Surgeon General during the Third Reich. Schreiber helped the OSS set up an experimentation facility at Camp King, a CIA site located near Frankfurt in the American sector of Allied-occupied Germany. Later, when Schreiber was transferred to the US by the CIA, Dr. Kurt Blome, the Third Reich’s former Deputy Surgeon General, who specialized in weaponizing bubonic plague, took over the program.

The book contains excerpts from a memorandum written by the Deputy Director of Central Intelligence at the time, Allen Dulles, in which he explains the need for “augmenting the usual interrogation methods” with the help of the German scientists. Dulles goes on to describe the “promising results” produced in interrogations involving the use of “light dosages of drugs coupled with hypnosis”, shock techniques, and other similar methods.