Wang Quanzhang's wife says he was in very good health at the time of his detention in July 2015.
Will Nguyen was beaten and detained during a protest over a long-term lease scheme for foreign firms.
A week ago, TEMP.Periscope infiltrated the computers of several stakeholders in an upcoming election.
More than 2 million are forced to work without pay, most of them for the country's regime, a report says.
