The humanitarian workers had travelled with a United Nations aid convoy, escorted by U.N. peacekeepers, to the eastern town of Rutshuru, captured by advancing Tutsi rebels last week in Democratic Republic of Congo's North Kivu province.
Camps previously run in the Rutshuru area by the U.N. refugee agency UNHCR, and housing at least 50,000 people, were found levelled and deserted when the aid convoy arrived.
"All the camps are empty. They have all left. All the shelters have been destroyed ... nothing remains," Francis Nakwafio Kasai, a field officer with the U.N. Office for the Coordination of Humanitarian Affairs (OCHA), told Reuters.
Last week's rebel offensive by fighters loyal to renegade Congolese Tutsi General Laurent Nkunda had ended with the declaration of a ceasefire after the insurgents reached the outskirts of the North Kivu provincial capital Goma.
Both Goma, still in government hands, and rebel-held Rutshuru were calm on Monday.
But aid agencies have called the humanitarian situation triggered by the recent fighting "catastrophic" and say that tens of thousands of civilians are roaming the hilly countryside unprotected, in need of shelter, food, water and medical care.
Kasai, who spoke at Kasasa camp near Ruthsuru, 70 km (45 miles) north of Goma, said humanitarian workers were trying to establish whether the camps' occupants were forced out, or had fled. Some may have sought safer areas, or returned home.
"There was very little left to determine what made the people leave. The building materials are gone, there are no belongings left on the ground," Sean Rafter, a logistics officer with the British medical charity Merlin, told Reuters.
"The concern at the moment is that the population has moved away and we don't know where they are ... People are no longer able to get medical care, food or water. Until we know their whereabouts, we're very concerned for their welfare," he added.
Civilians were seeking safety after fleeing attacks by Nkunda's fighters and killings, looting and rapes which the U.N. says were committed by retreating Congolese army soldiers.
U.N. agencies and humanitarian NGOs coordinated the aid convoy as African and Western governments sought to organise a regional summit this week to bring together the presidents of Congo and Rwanda to discuss the conflict on their common border.
PLAN TO REORGANISE U.N. FORCE
European, U.S. and U.N. envoys have criss-crossed the Great Lakes region in recent days, trying to prevent the newly resurgent Tutsi rebellion in the eastern Congolese borderlands from escalating into a rerun of Congo's 1998-2003 war.
After a weekend diplomatic shuttle that took them to Congo, Rwanda and Tanzania, the French and British foreign ministers called for more international aid for Congo's North Kivu.
Bernard Kouchner and David Miliband, who reported their findings on Monday to other European foreign ministers, are calling for a major reorganisation of the 17,000-strong U.N. peacekeeping force already deployed in Congo.
The U.N. force (MONUC), stretched across a nation the size of Western Europe, has been criticised by Congo's government and eastern civilians for failing to confront the North Kivu rebels.
"They have helicopters. They have 83 planes ... The problem is perhaps to have a wholesale change of the organisation of MONUC ... they have a robust mandate," Kouchner told reporters on the sidelines of the ministers' meeting in Marseille, France.
He said Europe was ready to support a reorganised U.N. force. France, which holds the rotating EU presidency, had last week proposed sending EU troops to east Congo but the idea encountered resistance from some member states.
Britain's Miliband told reporters in Marseille European ministers would look at how the European Union could support the U.N. operation in Congo diplomatically and politically.
"No-one has ruled out a military role," he adding, stressing that any help should be channelled through the United Nations.
The African Union, European Union and United States have recommended that Congolese President Joseph Kabila and Rwandan President Paul Kagame meet to discuss the conflict on their common border, possibly at a summit this week in Nairobi.
An estimated one million people have been forced from their homes in North Kivu by two years of violence that has persisted despite the end of the 1998-2003 war in the vast, former Belgian colony, which is rich in copper, cobalt, gold and diamonds.
Nkunda, who says his four-year-old bush rebellion aims to defend Congolese Tutsis, has offered to talk to the government. He accuses Kabila's army of backing Rwandan Hutu rebels in east Congo who took part in Rwanda's 1994 genocide. Congo has accused Tutsi-led Rwanda of backing Nkunda, a charge denied by Kigali.
By Hez Holland
- Reuters - Thomson Reuters Foundation
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