Humanitarian groups warn the fighting in the Democratic Republic of Congo is about to explode while the UN accuses Rwanda of backing rebels. Congolese rebels known as M23 said they have no plan to attack the main city of Goma, in eastern DR Congo. But the group has been fighting the Congolese army in the east of DR Congo for weeks now and they have already swept away defences in several strategic towns. The army appears to be struggling to contain the fighters. The UN has positioned most of its artillery to help defend Goma. The peacekeeper's mandate has always been to protect civilians but until now they have tried to avoid a fight.