BBC meets gang 'paid to join Boko Haram' in Niger
22 April 2014 Last updated at 06:37 BST
Members of a gang in Niger have told the BBC that they collaborated with radical Islamist group Boko Haram in return for money.
Nigeria's neighbouring countries - Niger, Cameroon and Chad - are fearful that the group's insurgency may spill over to their borders.
Thomas Fessy reports from Diffa.