Six books containing formerly classified documents about Kuomintang spymaster General Dai Li during the second Sino-Japanese war have shed light on many mysteries surrounding one of the world's largest intelligence apparatuses.
The books contain copies of documents handwritten by Dai, including his orders to underlings and telegrams and letters to his boss, Chiang Kai-shek.
Dai, who died in a plane crash on March 17, 1946, was infamous on the mainland because of his brutality towards the Communists during the 1940s. He was described by historian Frederick Wakeman as 'China's Himmler' because he led an 18,000-member spy system - the world's largest espionage organisation during the second world war.
Wu Shu-feng, a researcher at Taiwan's Academia Historica who worked on the project, said 15,000 pages of archival material had been edited into to six books, three already published and three due out by the end of the year.
All the archival material declassified by the island's intelligence authorities would be opened to the public in April, she added.
The project was given the go-ahead by the Ministry of National Defence's military intelligence bureau after it decided to declassify part of its archival material about the Kuomintang's campaign against invading Japanese forces.