Between 500 and 600 armed rebel militia forces loyal to Peter Gatdet are moving through Lakes State to Mapel military training centre, in Western Bahr el Ghazal, for integration into the SPLA.
The group arrived in Shambe on September 9 and continued on foot to Yirol two days later.
UNMISS has reported that the forces are moving with family members including several children and pregnant women.
Some 60 former child soldiers are part of the group.
Another rebel militia group, loyal to late leader Gatluak Gai, is also reported to be moving to Shambe to join the SPLA in Western Bahr el Ghazal.