Father Giulio Albanese of Misna: This is not the first masssacre of civlians

"If it is true, then those responsible will be punished ...but we cannot say if it is true or not," rebel leader Ernest Wamba dia Wamba told reporters.

The Roman Catholic missionary news agency, Misna, based in Rome, said the killings took place at the village of Mokobola, in the east of the country. It said entire families had been slaughtered, by machete or gun over a three-day period.

'Act of retaliation'

Rwandan soldiers, who support the rebels, are also reported to have taken part.

Misna editor, Father Giulio Albanese, told the BBC he believed the massacre was "an act of retaliation against the civilian population" for their support of the Mai Mai - a group Congolese nationalist partisans supported by President Laurent Kabila who are fighting the Tutsi rebels known as the Banyamulenge.

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The Mai Mai are reported to have launched an attack on rebels the day before the massacre in which several Tutsi soldiers had been killed.

Earlier rebel forces around the rebel stronghold of Goma denied that any killings had taken place. A local commander, Jonas Padiri, said the area was quiet and there had been no problems.

State of fear

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Misna, which reports for all 40 Catholic missionary orders working in Africa, said that the commander of the soldiers who carried out the massacre was a Rwandan known locally as Shetani, meaning the Devil.

Around 350 people were killed in a similar reprisal attack in the same area last August.

Father Albanese, said that tension was still high in the area and the civil population was living in great fear. He said the news had taken so long to emerge because people who break such information run the risk of being killed.