A group of activists in Hong Kong have raised concern about the whereabouts and condition of three health care activists in Changsha, Hunan who have been arrested by mainland authorities two months ago and not heard of since then.

Cheng Yuan, Wu Gejianxiong and Liu Yongze who worked for Changsha Funeng, a NGO working to improve the rights of people with HIV and viral hepatitis, were arrested on July 22 and charged with “subverting state power”.

But members of the Civic Party, League of Social Democrats and the Alliance in Support of Patriotic Democratic Movements who demonstrated outside the Beijing’s liaison office in Western, said lawyers or relatives have not heard from the trio since.

Vice chairwoman of the alliance, Chow Hang-tung, said the only information that authorities gave the family was a video tape of Cheng Yuan recorded by the officials.

“According to his wife, Cheng Yuan looks very weak and he is very thin compared to before he was arrested. We are very worried about the detention conditions since there is no access to them” Chow said.

We fear they maybe undergoing torture inside detention centres, the activist said

She said the authorities have not specified charges against them or what they did to get arrested.

Chow told RTHK’s Olivia Tam that people from across the world, from the US to Africa, have called for the release of the trio.

Over 200 international organisations and individuals have signed an open letter calling on China to release them, she said.