Vehicles went around town parading cut off heads that had been spiked on sticks

rebel official Jacques Depelchin

Rebel officials said that severed heads had been paraded around Bunia on the border with Uganda after violence erupted on Friday between the Lendu and Hema groups.

"Vehicles went around town parading cut off heads that had been spiked on sticks - it was horrible," rebel official Jacques Depelchin told Reuters news agency.

Officials say most of the dead have been taken off the streets and buried in mass graves.

Tensions

Tensions between the Hema and the Lendu, who share fertile land close to the Ugandan border, have existed for many years, but appear to have been exacerbated by the wider war in the country.

According to a number of reports, Lendu warriors armed with spears and arrows attacked the town's airstrip and radio station on Friday.

Gangs of Hema youths armed with machetes responded by attacking Lendu civilians on the streets and in their homes.

"There have been a lot of revenge killings. Many houses have been burnt down, entire families have been killed," Mr Depelchin said

Ethnic tensions between the Hema and Lendu have existed for decades. The Hema are traditionally pastoralist, while the Lendu are mainly farmers.

No Kabila connection

The two communities have periodically fought over fertile land.

Our East Africa correspondent says the outbreak of violence is not connected to the killing last week of President Laurent Kabila in the capital, Kinshasa, but the traditional hostilities have been exacerbated by the two-and-a-half year old war.

Some local aid workers accused the Ugandan army, which is backing rebels in the area, of stirring up trouble by giving support to the Hema.

This is denied by Uganda.

A statement by the Ugandan government says extra troops have been deployed to restore order in Bunia.