KIGALI, Rwanda — Mwasa Niyon Senga felt trapped as a first sergeant in the Democratic Forces for the Liberation of Rwanda, an armed group that terrorizes villages in the eastern Democratic Republic of Congo. As a Rwandan soldier during the 1994 genocide, Senga feared he would be arrested, and probably killed, as an enemy of the state if he returned to Rwanda from Congo. He had fled to Congo during the genocide as soldiers for the current government took control of Rwanda.