Chinese state media frequently treats Japan's atrocities of the past like breaking news of today. But lately, the steady flow of war history-related news has become a flood.

Amid fast-deteriorating Sino-Japanese relations, China's State Archives Administration recently re-opened case files from a Chinese military tribunal in 1956 and launched a dedicated websiteto publish summaries of confessions by 45 convicted Japanese war criminals.

Among the horrifying accounts posted online by Chinese authorities are confessions of raping countless women, burying people alive and performing human vivisections in China -- all handwritten by captured Japanese army officers after World War II and long sealed in the state archives in Beijing.

The Chinese government's target is clear.

"Since the Abe cabinet came into power in Japan," begins the online introduction to the confessions, referring to Japanese Prime Minister Shinzo Abe. "It has openly confused right and wrong to mislead the public, in an attempt to whitewash the history of external aggression and colonialism."

China and Japan have a dark history of conflict, including the nine-year Second Sino-Japanese War during which the contentious Nanjing Massacre took place from December 13, 1937 to March 1, 1938. Japanese soldiers committed mass murders and forced Chinese and Korean women into sexual slavery during the occupation of Nanjing.

But it was a more recent flare-up, say analysts, which brought the historic grievances back out into the open.

Relations between China and Japan became strained in 2012 when Japan claimed islands in the East China Sea.

China then declared in November 2013 an Air Defense Identification Zone over the East China Sea, imposing air traffic restrictions over the disputed area.

China's moves have made Japan and other nations in South East Asia nervous over it's expanding military and more assertive foreign policy, accusing China of trying to change the status quo.

(CNN)