STORY HIGHLIGHTS Julie Keith discovered letter from a Chinese labor camp inmate in her Halloween decorationsLetter detailed life in camp, such as grueling hours, verbal and physical abusesCNN eventually spoke to the inmate, who made products destined for the West ... After months of searching, through a trusted source and with some good luck, CNN found the man who says he wrote the letter that Keith found in her Halloween decorations. Released from the labor camp but afraid to be sent back, he agreed to his first television interview on the condition that CNN concealed his identity. "Mr. Zhang" -- as he would be called -- is a follower of the Falun Gong spiritual movement, branded by the Chinese government as an evil cult and outlawed since 1999. He claims he was detained by police several months before the 2008 Summer Olympics in Beijing and sentenced to two and a half years in the Masanjia labor camp in northeastern China. "For people who have never been there, it's impossible to imagine," he said. "The first thing they do is to take your human dignity away and humiliate you." Zhang recounted the systematic use of beatings, sleep deprivation and torture, especially targeting those like him who refused to repent. Some gruesome details are too specific to him to be reported. "Making products turned out to be an escape from the horrible violence," he said. "We thought we could protect ourselves, and avoid verbal and physical assaults as long as we worked and did the job well." Secret messages Moving forward with his plan to expose the horror in the camp, he secretly tore off pages from exercise books meant for political indoctrination sessions as inmates were barred from having paper. He also befriended a minor criminal from his hometown -- a monitor for the guards -- who managed to get him another banned item: a ball pen refill. Hundreds of camps By all accounts, Masanjia is but one of hundreds of labor camps in China borne under the laojiao -- or "re-education through labor" -- scheme. This is an excerpt from CNN. The original article can be found here.