KIBATI (Congo) - DOCTORS are struggling to contain an outbreak of cholera in a sprawling refugee camp near Congo's eastern provincial capital of Goma, as renewed fighting ignited fears that patients could scatter and launch an epidemic.

On Sunday, Congolese soldiers and rebels were seen less than 800m apart near Goma, where rebel leader Laurent Nkunda declared a ceasefire on Oct 29 as his forces reached the edge of the city.

Rebels and soldiers clashed on Thursday just north of the Kibati refugee camp, 12 km from Goma, and soldiers who retreated last week were digging in Sunday at a new frontline.

Some 50,000 refugees have crowded around Kibati, some taken into log cabins by villagers, others living in tents or hastily built beehive-shaped huts. Thousands who sleep out in the open huddled under plastic sheeting on Sunday as curtains of rain pounded down.

Doctors Without Borders said it treated 13 new cases of cholera in Kibati on Sunday and has seen 45 cases since Friday.

The agency's Dr Rafaela Gentilini said shortages of water and latrines were making the outbreak 'really dangerous.'

Dozens of people have died of cholera in recent weeks elsewhere in eastern Congo. Doctors also fear an epidemic north of Goma behind rebel lines, where access has been limited by fighting and rebels have driven tens of thousands of people from camps where outbreaks had been contained.

At the front line near Kibati, soldiers milled around Sunday, collecting pay, smoking marijuana and looking unconcerned about the rebels, who were gathering less than a kilometre away.

Intermittent gunshots crackled from the direction of government positions.

'I'm ready, ready to kill Nkunda!' said 1st Sergeant Claude Kazunga, 33, raising his AK-47.

'If they provoke us, we will push them back.' Other soldiers hoped for a more peaceful solution.

'The (heavy) weapons that are being fired around here, we are killing our own parents,' said Lieutenant Jean-Paul Briki.

'There must be negotiations.'

The fighting in eastern Congo is fuelled by ethnic hatred left over from the 1994 slaughter of at least 500,000 Tutsis in neighbouring Rwanda.

Nkunda, whose rebels launched an offensive Aug 28, first said he was fighting to protect minority Tutsis from Rwandan Hutu militants who participated in the genocide before fleeing to Congo.

Now he says he wants to 'liberate' all Congo from an allegedly corrupt government. He is seeking direct talks with his former comrade-in-arms, President Joseph Kabila, whose government says it will not negotiate with a war criminal.

In Kibati on Sunday, rain soaked two young brothers wearing rags and plastic sandals who said they had walked from Rugari, 28 km away.

Kasigue, who said he was 12 but appeared far younger, shivered as he clutched a clump of green onions and some electrical wire. His brother Gasaza huddled under a dirty plastic sheet. The boys were separated from their parents when fighting erupted and hoped to find them at Kibati.

'We've been walking since morning,' said Gasaza.

The UN Children's Fund says hundreds of children have lost their parents as more than 250,000 refugees have been forced from their homes in the last 10 weeks.

In Kibati, the International Red Cross distributed enough flour, oil and beans to feed 35,000 people for 10 days, and spokesman Luc Haas said more food will be distributed on Monday.

Earlier on Sunday, thousands of people packed churches in Kibati and Goma to pray for a halt to the fighting that saw rebels and pro-government militiamen executing civilians last week in what the top UN envoy to Congo has called war crimes.

But prayers went unheeded, as new fighting erupted 60km northwest of Goma, with rebels and Congolese soldiers firing mortars and rocket-propelled grenades in the village of Ngungu, UN military spokesman Colonel Jean-Paul Dietrich said. The rebels also were fighting pro-government Mai Mai militia around Ngungu, he said.

UN peacekeepers met with commanders of the three forces and persuaded them to stop after about six hours, Col. Dietrich said.

Rebels and soldiers also clashed briefly at two villages north of Goma, one near Kiwanja, where the alleged war crimes were committed.

UN officials are investigating killings in the last few days at Kiwanja, 80km north of Goma. They say residents first were terrorised by Mai Mai militia who killed people they accused of supporting the rebels - then the rebels won control and killed those they claimed had supported the militia.

Many victims were shot execution-style in the head, residents told wires agencies.

UN investigators said at least 26 people were killed, but the New York-based Human Rights Watch group says it believes as many as 50 people died. -- AP