BEIJING, May 8 (Xinhua) -- A 90 year-old Chinese woman has revealed her distressing past as a forced sex slave for the invading Japanese army during World War II.

By going public with her experiences of the Japanese atrocities,Zhou Fenying said she hoped to "preserve historic proof" and help to make people more aware of Japanese wartime crimes.

Zhou, a native of Yangjiayuan village, Rugao County in east China's Jiangsu province, was forced into sexual slavery by the invading Japanese army in the spring of 1930. She was 22 and had been married for nearly 10 years.

"When a group of Japanese soldiers scoured our village for women, I hid with my husband's sister under a millstone in our neighbor's house for a whole day," recalled Zhou, "we were paralyzed by fear when the millstone was finally removed and they tied us up."

The two women, along with at least 20 others, were sent to a brothel in the nearby town of Baipu, run by the Japanese military.They were raped daily by more than 50 Japanese soldiers and if they dared to resist, they were beaten.

"We were closely watched 24 hours a day," said Zhou, "there was no way of fleeing and our family could do nothing to help us."

Zhou added that she was so traumatized by the incident that she never stopped crying. As a result, she contracted a serious eye disease and eventually lost her sight.

She had served as a 'comfort woman' for two months, when a local town official redeemed her, in the hope of taking her as a concubine. Zhou firmly turned down his request and went back to her husband Ni Jincheng.

Seeking revenge, Ni joined the army in 1941 to fight the Japanese occupiers, but subsequently died later that year. He was posthumously named a war hero.

Zhou later remarried and gave birth to a son, Jiang Weixun. Jiang, now 62, said the whole family used to avoid mentioning his mother's horrifying experiences at the hands of the Japanese.

"Some relatives felt it was shameful," he said, "so when I was a child, she covered up that experience, fearing I might be looked down upon."

However, the recent death of a Chinese woman, similarly forced into sex slavery by the Japanese, gave Zhou the confidence to speak up.

"She burst into tears when I read her a local newspaper story about the death of Lei Guiying, the only person to have testified to wartime Japanese sexual slavery in Nanjing," recalled Jiang. He subsequently encouraged his mother to go public with her own experience.

Lei Guiying, who was raped by a Japanese soldier at the age of 13 and was later forced into working in a Japanese-run brothel in Nanjing for two years, died of a brain hemorrhage on April 25, she was 79.

Historians said her death marked the passing of one of the few known remaining victims of sexual slavery during Japan's invasion and occupation of China.

Chinese experts say less than 50 former Chinese sex slaves are still alive, although few have gone public with their experiences.

An estimated 200,000 women were forced to serve as sex slaves for Japanese forces during World War II.

The issue of wartime sex slavery re-emerged when Japanese Prime Minister Shinzo Abe suggested in March that no proof existed to confirm any of the claims that the Japanese military had forced women into working in brothels.

Now that one more brave victim of wartime sex slavery has come forward, all eyes are on those Japanese politicians who attempt to whitewash the country's wartime past, historians said, urging Japan to look squarely at history.

"My mother has finally stood up to testify to wartime Japanese atrocities," said Jiang, "she deserves the respect and support of all the Chinese people."