Merdan Ghappar was used to posing for the camera.
As a model for the massive Chinese online retailer Taobao, the 31-year-old was well paid to flaunt his good looks in slick promotional videos for clothing brands.
But one video of Mr Ghappar is different. Instead of a glitzy studio or fashionable city street, the backdrop is a bare room with grubby walls and steel mesh on the window. And in place of the posing, Mr Ghappar sits silently with an anxious expression on his face.
Holding the camera with his right hand, he reveals his dirty clothes, his swollen ankles, and a set of handcuffs fixing his left wrist to the metal frame of the bed – the only piece of furniture in the room.
The video of Mr Ghappar, along with a number of accompanying text messages also passed to the BBC, together provide a chilling and extremely rare first-hand account of China’s highly secure and secretive detention system – sent directly from the inside.
The material adds to the body of evidence documenting the impact of China’s fight against what it calls the “three evil forces” of separatism, terrorism, and extremism in the country’s far western region of Xinjiang.
Over the past few years, credible estimates suggest, more than one million Uighurs and other minorities have been forced into a network of highly secure camps in Xinjiang that China has insisted are voluntary schools for anti-extremism training.