United Nations experts have accused the Rwandan military of commanding Congolese rebel forces in their capture of the strategic city of Goma.
They said a top Rwandan commander travelled to Congo to oversee the offensive and hundreds of Rwandan troops fought alongside the M23 rebel fighters.
In a letter to a UN Security Council committee, the experts provided a day-by-day outline and photos backing their conclusion. The letter, obtained by The Associated Press, is a follow-up to a report preceding the capture of Goma that made similar accusations against Rwandan forces.
The M23 rebels held Goma, a provincial capital of one million, for two weeks before Congolese soldiers took back control on Monday.
A call to Rwanda's UN Mission seeking comment on the letter was not immediately returned. Rwanda has repeatedly denied assisting the rebels. M23 is made up of hundreds of officers who deserted the Congolese army in April. Since then the rebels have occupied vast swathes of territory in mineral-rich eastern Congo.
The rebels accuse Congo's president Joseph Kabila of failing to honour the terms of a 2009 peace deal that incorporated them into the national army, although most analysts believe that the origin of the rebellion is a fight over the country's vast mineral wealth.
The expert group said it has repeatedly concluded that the government of Rwanda and allies in the Ugandan government have "created, equipped, trained, advised, reinforced and directly commanded the M23 rebellion". "The information initially gathered by the group regarding the recent offensive and seizure of the North Kivu provincial town of Goma strongly upholds this conclusion," said the letter, sent to a committee that monitors sanctions against armed groups in Congo.
After deserting the army, M23 fighters seized a series of small towns and villages in the North Kivu province, where a good chunk of Congo's mineral wealth is found, culminating with the November 20 capture of Goma. The Congolese army fled in disarray and UN peacekeepers, whose mandate is to protect civilians, held fire.
The experts quoted several senior Congolese commanders and former Rwandan officers as saying the Goma offensive was under the overall command of the Rwandan army's western division commander, General Emmanuel Ruvusha, who personally went to Congo to oversee the operation.
The same sources were quoted as telling the experts that Col Sultani Makenga, an M23 rebel leader, joined Gen Ruvusha in leading the offensive. Gen Bosco Ntaganda, who is believed to be the leader of M23 and is wanted for crimes against humanity by the International Criminal Court, led rebel troops operating near the Rwandan border at Kibumba and in the Goma airport area, the sources were quoted as saying.