New violence has broken out in a volatile Tibetan region of western China, leaving eight people dead, an overseas Tibet activist group says. China's official Xinhua News Agency said a government official was seriously injured. The London-based Free Tibet Campaign said Friday police fired on hundreds of Buddhist monks and lay people who had marched on local government offices to demand the release of two monks detained for possessing photographs of the Dalai Lama, Tibet's exiled Buddhist leader. Xinhua did not mention dead or injured protesters, though it reported a riot outside government offices Thursday in the Garze Tibetan Autonomous Prefecture in Sichuan province's mountains near Tibet. It said that an official was "attacked and seriously wounded," and that police were "forced to fire warning shots and put down the violence."