NANJING -- Historical materials have been donated to a Chinese memorial hall as new evidence of war crimes related to the 1937 Nanjing Massacre perpetrated by invading Japanese troops.

The items include the wartime diary of Nishijo Eikaku, a Japanese soldier who witnessed the carnage of the massacre, and a photo collection containing 324 images of the Japanese forces occupying Nanjing and other locations in 1937, according to the Memorial Hall of the Victims in Nanjing Massacre by Japanese Invaders.

Daito Satoshi, from Japan, was the donor of the photo collection. He also provided the memorial hall with Japanese documents on wartime air defense facilities in Shanghai and Nanjing, and other items.

Notably, the hall received many photographs and documents concerning "comfort women," including a blueprint for the renovation of a "comfort women" station in Shanghai and physical examination forms from a Japanese military field hospital for "comfort women."

Previous research has shown that some 400,000 women in Asia were forced to be "comfort women" -- sexual slaves for the Japanese army during World War II -- and nearly half of them were Chinese.