The thousands of Yazidi women and children were taken prisoner in August 2014, when IS fighters overran their villages in northern Iraq with the aim to eliminate the Kurdish-speaking minority because of its ancient faith. Since then, Arab and Kurdish smugglers managed to free an average of 134 people a month. But by May, an IS crackdown reduced those numbers to just 39 in the last six weeks, according to figures provided by the Kurdistan regional government.