Activist and former independent candidate to the National People's Congress Liu Ping has been detained on suspicion of inciting subversion of state power after being taken away by state security officials last month.
Shanghai-based legal scholar Zhang Xuezhong was informed of the charges against Liu at a police station in Xinyu, in southeastern China's Jiangxi province, on Tuesday when he filed a request to legally represent and meet her.
No further information was given to him and his request to immediately meet Liu had been denied, Zhang wrote on a Sina Weibo microblog, which has since been deleted.
The East China University of Politics and Law scholar declined to speculate on what action might have led to the charges.
Nobel Peace Prize laureate Liu Xiaobo is currently serving an 11-year sentence on the same charges. Whereas Chinese criminal law allows for jail terms of up to five years, longer sentences can be imposed in cases considered serious.
Liu Ping was one of eight people who were taken from their homes in Xinyu by unidentified men on April 27, said Jiang Xuehua, a fellow Jiangxi activist from Changzhou. "They were preparing to go to Suzhou for the Lin Zhao anniversary, when they were nabbed," she said.
Two days later, hundreds of people commemorated  the 45th anniversary of Lin Zhao's execution at her grave site in eastern Jiangsu province. Lin, a Peking University student, had been killed during the Cultural Revolution for her unrepentant criticism of the Communist Party and has since become an icon for opposition to the party's rule.
Two of the people detained along with Liu have been released, Jiang said. One of them, Li Xizhen, shared on her microblog photos of bruises  from beatings she said she had sustained in police custody. Li could not be reached on the phone.
Liu's daughter, Liao Minyue, who on her microblog has documented several unsuccessful requests for information on her mother's fate, declined to comment for fear of harming her mother's case.
"Because the law doesn't require relatives to be notified for such charges, we actually don't know how many people have been arrested and charged," said Hangzhou-based lawyer Wang Cheng, who has previously helped Liu in legal matters.
He said he could so far only confirm that five people including Liu were still detained, but only the charges against Liu had been made known, he said.
Wang speculated that the arrests were linked to Liu's online campaign in recent months calling for the publication of officials' assets.
Liu, 48, a laid-off factory worker, gained prominence when her bid to run as a local candidate for the National People's Congress failed in May 2011 .
She had campaigned on raising local monthly retirement benefits by 200 yuan (HK$250), Jiang said.
At least two other people arrested with her in April, Wei Zhongping and Li Sihua, had helped her in her independent election campaign, Wang said.
A police officer at the Yuanhe district police station in Xinyu, who declined to disclose his name, said the station was handling the case and had confirmed that police were in contact with Liu's family on unspecified charges.
He said that for legal reasons, he could not comment on charges against Wei Zhongping, Li Sihua or others.