Most, like Bakhita, are renamed, obliged to become Muslims, and then forced to marry their captor or herd his animals.

ECONOMIST: Charities who buy slaves their freedom may end up doing harm

Lemlem Ghebru's two daughters, aged 14 and 15, were freed when their captor's base in east Sudan was stormed by security forces.

BBC: Eritrean girl: I thought kidnappers would kill us

The case of the three Cleveland women who have escaped their captor after so long is inspiring and offers hope for other cases.

CNN: Most missing person cases don't have happy ending

"There can be such a wide range of abuse that a victim who is no longer viciously abused may feel gratitude" towards their captor, says Peter Suedfeld, professor emeritus of psychology at the University of British Columbia.

BBC: Magazine

One thing they could count on was that their alleged captor would never let them out.

CNN: SHARE THIS