Some of them told Al Jazeera they have been held in Chinese internment camps as part of the country’s crackdown on Muslims.
Al Jazeera has heard harrowing new testimony from people who say they were detained and tortured in camps in China.
Many have refused to reveal their identity, saying they fear their relatives may be persecuted.
According to activists, more than two million people have been held in China’s internment camps in Xinjiang province.
Most are Uighurs, but there are also people from other minority groups such as ethnic Kazakhs.
Al Jazeera’s Osama Bin Javaid met some of them in Almaty, Kazakhstan’s largest city.
Watch Part Two of our special series here.