CHRISTIAN Solidarity International, a non-governmental organisation involved in a controversy over Sudan’s slave trade, said on Wednesday it had freed almost 1400 slaves in May. CSI has liberated a total of 9112 Sudanese slaves since the start of its campaign in 1995. The Zurich-based NGO frees the slaves by buying them. The method has been condemned by the UN Children’s Fund (Unicef), which has argued that the CSI is perpetuating the slave trade without attacking the problem at its root — Sudan’s civil war. According to CSI, there are tens of thousands of black slaves in northern Sudan subjected to torture, mistreatment, rape, excision, and forced religious conversion and forced labour. CSI did not say how much it paid for the release of the 1387 slaves, all members of the Dinka tribe freed between May 17-22. In the past it has paid the equivalent of 50 dollars per slave via intermediaries.