plotting against the chinese government and the crime of separatism and they demanded a confession. >> just confess, just admit what you have done. it is good for you. >> reporter: now, for the very first time, cnn has spoken to a former chinese police officer who claims his job was to arrest and extract confessions from ethnic uyghurs in xinjiang. >> translator: some cops would play the good cops and some would play the bad cops. after we beat them, we would offer them a cigarette. >> reporter: did you have to be the bad cop sometimes? >> translator: of course. >> reporter: the man who asks to be called jiang says he worked more than ten years as a cop, before fleeing china after growing disillusioned with the ruling communist party. i met him in a european country. he wore his police uniform to authenticate his story but does not want to be identified to protect himself and relatives that are still in china.