The victims are reported to have been killed at the village of Magunga on the shores of Lake Tanganyika by local mercenaries, allegedly in the pay of the Rwandan Government.

Previous killings

The massacre - the latest outbreak of inter-ethnic fighting in the region - is said to have happened early on Monday.

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It follows a report earlier this month by the Italian Missionary News Agency that 100 people had been massacred in villages in eastern Congo.

The same organisation told of 500 civilians being shot during a reprisal by Rwandan-backed rebels in the new year.

The latest reported massacre, like the others, cannot be independently verified.

But villagers have told a journalist that in the Fizi area south of Uvira, Rwanda has fallen out with its former allies, who are known as Banyamulenge.

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The villagers said the Rwandans had employed local Mai Mai tribal fighters who killed Banyamulenge villagers.

Magunga's Village Chief Samson Muhizi said: "They encircled the village and started to kill people with machetes."

He said: "We want an international force to stop the genocide being conducted against us by the government in Kigali."

'Total fabrication'

In a statement from its Defence Ministry, Rwanda said the report was a "total fabrication" and that no massacre had occurred.

It blamed the "lies" on a small disaffected section of the Banyamulenge who had separated from the mainstream of the Congolese rebel army, the Congolese Rally for Democracy.

It said Rwanda would never be associated with the Mai Mai.

'Horrific crimes'

"The Mai Mai militia has committed some of the most horrific crimes of genocide ... in Congo", it said.

"Under no circumstances would the Rwandan Government sponsor a criminal gang to perpetrate the same kind of crimes."

In the region, the Mai Mai tribal fighters are guns for hire.

They initially supported Rwanda and Uganda and their rebel allies when they reinvaded Congo last year, but have since turned against them.

Switch of allegiance

Correspondents say if the reported reasons for the latest massacre are true, it would appear that some of these mercenaries have switched allegiance again.

Large parts of the the Congo are now in the hands of forces supported by Rwanda and Uganda.