Nigeria is struggling to bring home an estimated 20,000 girls trapped in the sex trade in Mali, who are reported to be kept in appalling conditions.

Officials say collusion between law enforcement agents and traffickers is hampering the rescue efforts.

Reports also indicate that despite the presence of Malian soldiers deployed in numbers, to bring the situation under control in Kokoyo, armed men arrived in huge numbers and made it clear, that the Nigerians trying to rescue their citizens trapped in the sex trade are not welcome in that region, and eventually the delegation had to leave.

Activists who have been with the girls, say they also face such threats from the traffickers every time.