THE only surviving sex slave in Nanjing who came forth to testify about the Japanese invaders' "comfort woman" atrocity was in critical condition after suffering a brain haemorrhage.

Lei Guiying, 79, was forced to be a comfort woman when she was 13 years old during the invasion of China by Japanese troops in the World War II, the Oriental Morning Post reported today. She was the first and only known surviving victim in Nanjing who can confirm the history and fate of the comfort women.

Li Cuilan, Lei's daughter-in-law, said Lei began vomiting from 7pm on Sunday. "She fell unconscious when we sent her to the hospital," Li said.

Lei took a bottle of potassium permanganate when escaping from sexual slavery 64 years ago. The chemical was used by the Japanese to wash and disinfect the women.

The chemical was typically used in sex slave quarters, according to former Japanese soldiers and documents, and can be important evidence to confirm the history of comfort women.

About 200,000 Chinese women were forced into sexual slavery nationwide during the invasion by Japanese troops. Most women have died, and have not come forth for fear of prejudice. Only 84 comfort women have been identified on the Chinese mainland.

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