NANJING, March 16 -- China plans to protect buildings once used as a notorious military brothel by invading Japanese troops during World War II to serve as a reminder of war crimes.

Experts confirmed the seven buildings, located in Liji Alley of Nanjing City, capital of east China's Jiangsu Province, as the original site of two Japanese-run "comfort woman" stations, the largest of their kind in Asia.

One station housed Korean women, who served Japanese soldiers, and the other, with Japanese women, was designed for Japanese officers, said Jing Shenghong, a history professor with Nanjing Normal University.

"It's of great historical importance to have these buildings protected for the whole world to remember the crimes of war," Jing told Xinhua on Sunday.

The Nanjing city government has sent experts to check the buildings and draft plans for protection.

Japan invaded China in 1937 and occupied much of the country's territory, including Nanjing, before it surrendered in 1945.

Historians estimated 200,000 women, mainly Chinese and Korean, were forced to serve as sex slaves for Japanese forces during World War II. But it is believed there may be many more who have remained silent.

Lei Guiying, a Nanjing native and one of the few remaining known comfort women who survived the war, died of a brain hemorrhage on April 25, 2007. She was 79.

In recent years, Japan's right-wing politicians have denied that Japan had played a state role in the issue, saying the "comfort women" were "transported by private businessmen."

But Japanese documents revealed by Jilin Provincial Archives regarding "comfort women" show in detail the Japanese government and military's role in abducting, trafficking and forcing women to provide sex to Japanese soldiers.