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.

Kigali’s support of former Democratic Republic of Congo president Joseph Kabila could complicate peace talks, while Goma, the capital of North Kivu Province, is under siege by the M23.

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?