Disputes - international: the effects of Sudan's almost constant ethnic and rebel militia fighting since the mid-20th century have penetrated all of the neighboring states; as of 2006, Chad, Ethiopia, Kenya, Central African Republic, Democratic Republic of the Congo, and Uganda provided shelter for over half a million Sudanese refugees, which includes 240,000 Darfur residents driven from their homes by Janjawid armed militia and the Sudanese military forces; Sudan, in turn, hosted about 116,000 Eritreans, 20,000 Chadians, and smaller numbers of Ethiopians, Ugandans, Central Africans, and Congolese as refugees; in February 2006, Sudan and DROC signed an agreement to repatriate 13,300 Sudanese and 6,800 Congolese; Sudan accuses Eritrea of supporting Sudanese rebel groups; efforts to demarcate the porous boundary with Ethiopia proceed slowly due to civil and ethnic fighting in eastern Sudan; the boundary that separates Kenya and Sudan's sovereignty is unclear in the "Ilemi Triangle," which Kenya has administered since colonial times; while Sudan claims to administer the Hala'ib Triangle north of the 1899 Treaty boundary along the 22nd Parallel; both states withdrew their military presence in the 1990s, and Egypt has invested in and effectively administers the area; periodic violent skirmishes with Sudanese residents over water and grazing rights persist among related pastoral populations along the border with the Central African Republic
Illicit drugs: