Baikyi-sa was the premier terrorist group in Korea from 1945 until 1950. It's members worked for the US CIC as informants, assassins and agents provocatuers and more significantly, the CIC provided funds and training to Baikyi-sa. Given below is an English abstract of a paper publsihed in Seoul - http://www.pajooyom.com/eungtaek.htm, which includes the whole text of Major Cilley (US CIC) secret reports on Baikyi-sa.
Baikyi-sa was involved in several assassinations and assassination attempts - including one on Kim Il Sung. What roles did the US CIC play in these terrorust acts?
Baikyi-sa was established in December 1945 in Seoul by Yum Ung Taik. Yum was born in Pyongyang 1902 and attended the Sun-rim School of Commerce in Seoul. He went to China and enrolled in the Nakyang branch of the Nanking Military Academy in 1934. Kim Gu talked Chiang Kaisek into allowing a special class for Korean cadets at the Nakyang branch and the first class of Koreans started in December 1933.
There were more applicants than the school could accept and Kim Gu, Lee Chung Chun (李靑天 - Kim Gu's army commander) and Kim Won Bong (金元鳳 - Yiyul-dang chief) personally interviewed and selected candidates. Yum Ung Taek was recommended by Sin Yik Hee and interviewed by Lee Chung Chun.
The Korean cadets were paid 11 won a month by Chiang Kai Sek's government. However, the cadets were being paid much less than their allowance and they rioted suspecting corruption of the school administration. Yum was expelled and escaped to Sin Yik Hee's house in Nanking to avoid arrest and punishment. Sin Yik Hee got Yum a job as a postal inspector in Nanking under an fake Chinese name - Yo Chun Taik. Shortly thereafter, Yum joined Chiang's Namyi-sah, a covert action unit under Chiang's direct control.
Namyi-sah sent Yum to Manchurian on a spy mission but he was caught the by Japanese military police. Yum was tortured and as a consequence of the torture, his eyesight began to deteriorate and eventually, he became totally blind in 1948. For this reason, he was called the Blind General by the Americans. Yum told his US CIC handlers that he was arrested by Mao's forces and that it was Kim Gu who fingered him to Mao's security. Yum was turned and became an informant for the Japanese police. He was sent to Pyongyang to spy on Korean nationalists in that region. Yum married Choe Sung Ryul (崔成律), a graduate of Nara Women's High School in Japan, from a prominent pro-Japanese collaborator. Yum frequented Young Myon Sah, a Buddhist temple in Pyongyang - a gathering place of Korean nationalists. Its master monk, Park Go Bong, was a former independence fighter and many Koreans came to him for guidance.
In August 1944, Yum organized an anti-communist group, Daedong-dang, of dissident students and youth in Pyongyang. After liberation, Daedong-dang became a terrorist organization. Its first victim was Hyon Jun Hyok, the chaiorman of SOuth Pyongahn Province Communist Party. Hyon was gunned down in Pyongyang in September 1945 by Baik Kwan Ok and other members of Daedong-dang. Yum was arrested by the Soviet security police but was released because of insufficient evidence linking him to the murder. Yum and his associates fled to Seoul in November 1945. It is recorded that Yum confronted Arakawa Takejo at the Seoul rail station; Arakawa was the Japanese military police who had tortured Yum.
Yum renamed Daedong-dang Baikyi-sah in the late 1945. Oh Dong Jin, a rich merchant, donated a former Japanese mansion in Gungjung-dong for Yum and Baikyi-sah. (This mansion later became the main safe-house for partying for the Korean CIA and Park Jung Hee was killed there by his CIA boss Kim Jae Gyu while being entertained by college coeds on October 26, 1979.) Belatedly, the Soviets learned the truth about Yum's involvement in Hyon's assassination and arrested his wife. Choe, who was tortured and lost her unborn baby while in prison. Upon her release, she escaped to Seoul and got reunited with her husband in March 1946.
Yum got reconnected with his old mentor, Sin Yik Hee and other right-wing extremists. Recently declassified US documents show that Yum provided intelligence to the US CIC agents in Seoul and had received financial and other supports from the Americans, Baikyi-sah trained and dispatched spied to North Korea and also, conducted political terrorism in South Korea. Yum's agents infiltrated military, police and civil organizations in South Korea and collected intelligence for the US CIC.
In the late 1945, Yum kidnapped Kim Doo Whan, the military chief of the Korean Communist Party and the son of Gen. Kim Jwa Jin, a famous Korean independence fighter. Yum told Kim that his father was killed by Communists - actually, he was killed by his own men working for the Japanese - and persuaded the younger Kim to turn against Communists. Kim Doo Whan became a notorious anti-red crusader thanks to Yum. It goes without saying that Kim Doo Whan took orders from Yum.
Sin Yik Hee persuaded Yum to become the military arm of his Provisional Political Special Action Committee, a loose association of the former members of the Korean Provisional Government in China. This organization was headed by Sin Yik Hee; Yum was its military chief. Cho Jung Suh was its chief of operations. It was Sin Yik Hee who had Yum working for the US CIC. Lee Soon Yong was a US CIC sergeant in Korea. Lee was a Korean American and served with the US military during World War II. (Lee, later, served as Minister of Interior for Rhee Syngman).
Gen. Hodge, the US military commander of Korea, sent Lee to Sin Yik Hee with the message that Sin's Action Committee would be disbanded unless Sin agreed to provide intelligence on North Korea. It was agreed that Yum's Baik-yi-sah would work for Gen. Hodge collecting intelligence on communists as well as non-communists in Korea. Yum's American contact was US Army Major Whittaker who headed the US CIC detachment in Seoul at the time. Major Whittaker acquired a training camp for Yum. The camp was a remote resort formerly owned by a Japanese capitalist.
By May 1946, Yum had ten agents trained at his CIC-provided training camp. They were sent to North Korea, two per province. Their mission was to collect information on military installations, strength, weapons and so on. Major Whittaker gave Yum a list of specifics that the Americans wanted. Yum's fortune fell with the establishment of the Republic of Korea in 1948. The US CIC's role diminished and the Korean government established its own spy agency - HID. Some 100 of Yum's agents joined HID and Yum's training center was taken over by HID in 1948.
In February 1949, an emissary of Gen. Willoughby, Gen. MacArthur's intelligence chief, came to see Yum with an urgent request for intelligence on North Korea and future cooperation. Consequently, the Korean Liaison Office - KLO - was established on June 1, 1949. The few remaining members of Baikyi-sa became the founding members of KLO.
In June 1950, Yum was captured by the People's Army in Seoul and was killed in an American bomb raid while being transported to Pyongyang.