Ethnic Uighurs walk as Chinese army troops patrol outside the main mosque in Urumqi in China's Xinjiang Autonomous Region July 10, 2009. Ethnic tensions in China's far-west Xinjiang shift from the streets to mosques of the regional capital on Friday, with many Uighur Muslims saying the authorities would not let them observe their main day of prayer. REUTERS/Nir Elias (CHINA CONFLICT RELIGION POLITICS)