The U.N. Integrated Regional Information Networks reported Monday that the weekend clashes involved the Sudan People's Liberation Movement and fighters from Abyei's Misseriya community.

Both sides blamed the other for the outbreak of violence in the Al-Mayram region of Abyei, and the SPLM also chastised the Sudanese government for allegedly arming the Misseriya.

The United Nations said in a statement that oil revenues in Abyei have been fought over for some time amid a power vacuum formed amid disagreements over the implementation of a ceasefire agreement that supposedly ended Sudan's civil war three years ago.