HARBIN, Aug. 12 -- Newly published archival files in northeast China's Heilongjiang Province on Tuesday revealed Japan organized multiple large-scale immigration campaigns in the region during its invasion in World War II.

The Heilongjiang Provincial Archives unveiled 96 files on the Japanese invasion of northeast China, said Qi Xiujuan, head of the archives.

Twenty-one were published for the first time, including immigration policies and acts, records of immigration categories, immigration plans and implementation, and land records, Qi said.

According to the files, Heilongjiang Province served as an important resettlement region for Japan's mass immigration plan due to its abundant resources and strategic importance.

From September 1931 to January 1941, Japanese invaders set up 89 mass immigration regions in northeast China, 69 of which were in Heilongjiang.

The archives showed that nearly 130,000 Japanese organized by official Japanese immigration agencies resettled in Heilongjiang Province during Japan's invasion. Most of them were repatriated to their homeland before September 1946.

"This kind of organized, planned and forced land reclamation violated and trampled on Chinese sovereignty," said Qi, adding that the archives have provided hard evidence of major land grabs by the Japanese in China.

The Heilongjiang Provincial Archives also published many other files related to comfort women and live victims used for bacteriological experiments.