HONG KONG - A second blind Chinese activist has escaped state custody, a Hong Kong human rights group said, three months after dissident Chen Guangcheng embarrassed Beijing's vast security network by breaking out of detention and obtaining US protection.

Chinese Citizens' Rights Protection Alliance said 57-year-old Li Guizhi, detained at the border in southern Shenzhen city for trying to enter Hong Kong to join a large pro-democracy protest on July 1, had escaped custody this week with the help of her relatives.

Li had been petitioning authorities for years to investigate the death of her son, who died suddenly in 2006 and was quickly cremated, Liu said. She never saw her son's dead body.

She had wanted to enter Hong Kong to petition her cause at a march held to mark the anniversary of Britain's 1997 handover of the territory back to China, Liu added.

Li was subsequently held in a hotel room in Hebei province in northeast China weeks later and, when her guards were dozing, the relatives sneaked her out of the building, Liu Weiping, a spokesman for the alliance, said late on Thursday.

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