In a push to prepare for the Three Gorges Dam, Fuling - the city made famous by the book River Town - has enlisted prison labour to build roads and other infrastructure. On a recent visit to the region, scores of prisoners with closely cropped hair and wearing blue uniforms toiled on roads leading to housing for resettled migrants in the upper reaches of the town. Local residents said they frequently saw uniformed guards marching prisoners between work sites, even in populated areas. According to state media, the government has ordered local authorities to speed up preparation work, including relocation and clean ups, in the region to prepare for the rising waters of the Yangtze River next year. Fuling, administered by Chongqing municipality, has a population of more than one million in its urban and rural areas. The nationwide 'Strike Hard' campaign against crime and a local anti-crime drive called 'Tempest 10' have swelled prison populations in Chongqing, providing the labour force, sources said. Western human rights groups criticise the use of prison labour in China and some foreign companies have sought to ensure middlemen do not subcontract manufacturing to prisons. Fuling, more than 100km from Chongqing, is one of the last settlements upstream from the project where large numbers of people will be evacuated ahead of rising water levels. Author Peter Hessler, who spent two years in Fuling as a Peace Corps volunteer, described the town in his best-selling book, River Town. 'During the day Fuling was a dirty river town and you could see that much of it had been built too quickly, but at night all of the flaws disappeared,' he wrote.