Father Karlo Kaw preaches during a Palm Sunday Mass at the Catholic Church in Abyei, a contested region along the border between Sudan and South Sudan. Under a 2005 peace agreement, the region was supposed to have a referendum to decide which country it would join, but the two countries have yet to agree on who can vote. In 2011, militias aligned with Khartoum drove out most of the Dinka Ngok residents, pushing them across a river into the town of Agok. Yet more than 40,000 Dinka Ngok have since returned, with support from Caritas South Sudan, which has drilled well, built houses, opened clinics and provided seeds and tools for the returnees. Yet violence has continued, with a March 1 militia attack killing four residents, according to the United Nations.