In Photos: The Secret World Of Modern Slavery

Mai, 16, trafficked from Vietnam into China to be sold as a child bride

I was a good student. But my parents could no longer afford to send me to school, so they put me to work in the fields instead. One day I got chatting to a guy on Facebook. He said he was a police officer and that he could find me better paid work in China. I went to meet him, but a group of guys bundled me into a truck and drove into China. When we stopped, I ran for it. After a couple of days, some women took me to the local police and I was able to come back to Vietnam.

Photo: Abbie Trayler-Smith for the Guardian