A selection of written confessions by Japanese war criminals after World War II has been published in book form in China, with most of the archives available to the public for the first time, the State Archives Administration said on Tuesday.

Japan surrendered unconditionally in 1945.

From 1950 to 1956, 1,109 Japanese war criminals remained in prison in Fushun, Liaoning province, and Taiyuan, Shanxi province. The book includes photocopies of their handwritten confessions and detailed records of their interrogations and trials. The documents serve as irrefutable evidence of Japan's heinous crimes against China during the war, the administration said.

The written confessions detailed crimes such as the killing, enslavement and poisoning of Chinese people. The prisoners also confessed to using bacterial and chemical weapons, conducting biological tests on live humans and setting up military brothels with sex slaves for the Japanese army.

The book includes confessions by 842 prisoners, compiled in 120 volumes. The first 50 volumes were published in August 2015.

The book, published by Zhonghua Book Co, comprises the original photocopied texts in Japanese, along with supplements, corrections, postscripts and the text of Chinese translations made at the time. English translations of abstracts are presented before each written confession.