 He followed Riek Machar when he became reconciled with the Sudan government in 1997, joining the SSDF.Major General Tito Biel led SSDF forces in 1998/1999 in clashes with Sudan Armed Forces (SAF) troops and militia under Major General Paulino Matiep.By April 1999 Tito Biel's SSDF forces in Western Upper Nile were cooperating with the Sudan People's Liberation Army (SPLA) forces in Bahr el Ghazal, who were supplying arms.