The practice, used since the 1980s to help fill the hermit kingdom’s coffers, has reportedly accelerated under Kim Jong-un, who took power following the death of Kim Jong-il, his father, in 2011. Until 2012 there were thought to be up to 65,000 North Korean workers around the globe, often in terrible conditions. That number has since risen to around 100,000, activists told The New York Times.