Chinese Human Rights Defenders (CHRD) reports that two dissidents, Hua Chunhui and Wei Qiang, were sent to ‘re-education through labour’ camps, virtual forced labour camps, without trial or an opportunity to defend themselves.

Wei was taken into custody 50 days ago for supporting the Jasmine Revolution.

Zhu Yufu, 59, has been on the forefront of the struggle for human rights. He has been accused of “inciting subversion of state power” in Zhejiang province, after calling for peaceful protests like those in Arab nations. In 2007, he had been sentenced to two years in prison. He was detained again in February.

Lawyer Jin Guanghong disappeared on Tuesday. He had signed Charter 08 and defended members of the outlawed spiritual movement Falun Gong.

Tang Jinglig and lawyers Jiang Tianyong and Teng Biao also disappeared along with human rights activist Li Tie, who had been jailed on 15 September 2010 for “subversion”.

According to the CHRD, at least 40 people have been illegally detained in the country. At least 18 have simply “disappeared” into police custody without a trace, like well-known artist Ai Weiwei who was taken away by police on 3 April.

Hong Kong’s Wen Wei Po newspaper has reported that Ai is being held for tax evasion and that he “confessed”.

Ai’s family, which has not been informed by police of his fate, insists that charges of economic crimes are just a pretext, the consequences of his notoriety and widespread international outcry over his arrest, which Beijing puts down to alleged violations of economic laws.

In the meantime, spray-painted stencil drawings of Ai Weiwei have appeared on two sections of pavement and footbridge walls in Central and Sheung Wan.

The stencils carried Ai's image and the message ‘Who's afraid of Ai Weiwei?’ (pictured). Police are investigating the case, treating it as a criminal offence.