Abyei clashes (May 2008)
Sudan's army and southern forces clashed over Abyei town, burning much of it and displacing tens of thousands. The fighting nearly derailed the 2005 peace deal that ended Sudan's civil war.
A temporary ceasefire and international arbitration followed, but the dispute remained unresolved.
Abyei's final status was left for later negotiation, setting up the current deadlock.
Shows how Abyei has repeatedly been the flashpoint where Sudan and South Sudan nearly return to war.
