Witnesses said several hundred people slipped into the camp shortly after midnight and set about the tents with knives, clubs, machetes and guns. Some of the dead, not yet buried the following day, looked as if they had never woken up. They lay in the remains of their plastic sheeting tents, in family groups huddled together for warmth. One boy had the lower part of his face sliced off.
The charred remains of clothes and cooking utensils lay on the ground where several tents had been burned. Maize and beans spilled out of melted plastic buckets.
A day after the attack, a young man stood staring in horror at four mutilated bodies. He muttered the word "genocide". When asked to elaborate, he smiled wearily and turned away.
There is little doubt that those who carried out the massacre were Rwandan Hutu militiamen. The victims were refugees from the Masisi region in neighbouring Congo-Zaire. They were of ethnic Tutsi origin; most of them had fled their homes in 1996 when an alliance of Rwandan Hutu fighters and Zairean army soldiers carried out widespread killings there.
"This has always been the strategy of these guys. They carried out the genocide here, they carried out the genocide in the Congo. They think they are going to come back here and complete the genocide," the military commander for north-west Rwanda, Colonel Kayumba Nyamwasa, said at the weekend.
In 1994, officials from the extremist Hutu leadership, supported and assisted by the army, specially trained militiamen (known as interahamwe) and large numbers of civilians, killed around 800,000 Tutsis and Hutu opponents of the regime.
Almost 2 million people who fled Rwanda in fear of reprisals for the genocide have now returned home, the bulk of them since late last year.
Rwandan officials say large numbers of returnees, particularly in the north-western provinces of Ruhengeri and Gisenyi, have taken up arms and joined the interahamwe, who were able to retrain, re-arm and recruit in the refugee camps in what was eastern Zaire.
Since the beginning of May, bands of interahamwe have stepped up their campaign of violence in the north-west, long the heartland of Hutu extremism, attacking military targets, local officials and now a refugee camp. They are becoming increasingly bold. The country's powerful vice-president and defence minister, Paul Kagame, said recently that some of their tactics were suicidal.
The Rwandan army is hard put to contain the violence. Major General Kagame acknowledged that many soldiers were dying.
But the army has also been strongly criticised for the intensity of its response to interahamwe attacks. Human rights groups say large numbers of civilians are being killed in military operations. Military officials say that the almost exclusively Hutu local population is largely sympathetic to the militiamen. They say they often cannot tell the difference between fighters and civilians. Local people in the region speak of indiscriminate killing by the army.
In what has become a familiar pattern, local Hutus fled the area following the attack at Mudende camp. There have been reports that an unspecified number of Hutus were killed in reprisal attacks by Rwandan Tutsi civilians thought to be from another camp nearby. One local Hutu man said anyone who went outdoors during the night of the attack was shot. The following day Hutu homes were burned and there were reports of pillaging.
"They were doing our job for us," one soldier said when asked to respond to the reports.
The most pressing issue now is what to do with the remaining 8,000 refugees from Mudende. The UN High Commissioner for Refugees intends to discuss the issue with the governments of Rwanda and the Democratic Republic of the Congo (Congo-Zaire). The UNHCR's spokesman in Rwanda, Paul Stromberg, said: "We'll have to find a place where they can be cared for in conditions of security."
He added that the conditions were not right for them to return to Masisi. In the past month several thousand more ethnic Tutsis have had to flee attacks by a combined force of Rwandan Hutu militiamen, backed by former Zairean soldiers and other rebel groups.
To complicate matters, Masisi is thought to be the main base for thousands of the militiamen operating in Rwanda.
The minister for reconstruction and emergency planning of Congo-Zaire, Etienne Richard Mbaya, who visited Mudende camp on Saturday with a UNHCR delegation to discuss what should be done, said his government wanted the refugees home. But he admitted there were risks.
"The whole region is like a volcano. I don't know where the situation is most dangerous, in Masisi or elsewhere," he said.
t Kinshasa (AP) - A UN team arrived to begin an investigation into alleged massacres of Rwandan refugees by soldiers of Congo-Zaire President Laurent Kabila.
After months of delay, UN Secretary-General Kofi Annan was forced to name a new team leader and change the investigators' mandate to win cooperation from Mr Kabila's government, which took power in May after an eight-month rebellion that ousted President Mobutu Sese Seko.