Liu has been in prison before and also served three years in a labour camp for calling for the release of demonstrators after the Tiananmen Square protests. These camps have been used to get rid of journalists who accuse local officials of corruption, petitioners who seek redress for police brutality and anguished parents who want to know why so many children died in shoddily built schools that collapsed during last year's earthquake. Accurate figures are hard to come by, but another leading dissident, Harry Wu, claims that between three and five million people are being held in labour camps. (Read more)