Beijing has long claimed to be confronted with "religious extremist forces" and "violent terrorists" in Xinjiang, a vast region one-sixth of China's land area. Xinjiang has a population of 18 million and is home to numerous Turkic-speaking Muslim ethnic groups, of which the Uighurs, numbering eight million, are the largest. (The second largest group is the Kazakhs, with 1.2 million.) The percentage of ethnic Chinese (Han) in the population has grown from 6 percent in 1949 to 40 percent at present, and now numbers some 7.5 million people