The rebels continued advances in eastern Congo despite their own announcement of a cease-fire. The U.N. secretary-general called for them to lay down their guns and agree to mediation.

Rwandan backed rebels have entered the city of Goma, a key city in neighboring Democratic Republic of Congo. Could the mineral rich region be in danger of tipping into all out regional conflict?

Rwanda's ally Uganda, unhappy about another rebel group in DR Congo that threatens its security, has also been accused of helping the M23 - with its officers also spotted at Tchanzu. The UN experts say Uganda has also supplied weapons, hosted rebel leaders and allowed cross-border movements of M23 fighters - accusations Kampala denies.