At least 140 people have been killed and more than 800 injured in rioting in western China’s volatile Xinjiang region.Officials said the death toll was likely to rise. The unrest swept through Urumqi, the capital of the mainly Muslim region, on Sunday. Hundreds of people were arrested. Demonstrators said police cracked down violently on a protest by members of the Uyghur ethnic minority that began peacefully. The government blamed Uyghur exiles for stoking the unrest. The demonstrators had gathered to demand justice for two Uyghurs killed last month during a fight with Han Chinese co-workers at a factory in southern China. The Xinjiang regional police chief said the World Uyghur Conference used the factory incident to distort the government’s ethnic and religious policy and stir up conflict. He said the Internet had been used to spread rumours about the incident. Uyghur protestors are angry about government policies and the economic dominance of the Han Chinese. Xinjiang, in the northwest, is the doorway to China’s trade ties with central Asia, and is rich in natural gas, minerals, and farm produce. Many Uyghurs say they see little of this wealth. Italian president Giorgio Napolitano raised the issue of human rights when he met his Chinese counterpart Hu Jintao in Rome. Napolitano said the economic and social progress taking place in China brought fresh demands in terms of human rights.