A Democratic Republic of Congo rebel leader has threatened to resume hostilities if the government does not do more to protect ethnic Tutsis.
The victims of the massacre were buried in a mass grave
General Laurent Nkunda was speaking after the massacre of more than 150 Tutsis at a refugee camp in Burundi.
Both Burundi and Rwanda have made similar threats, raising fears of renewed conflict across the region.
Security has been increased in the border town of Bukavu, which Gen Nkunda briefly seized in June.
He told the BBC that the massacre was a "planned genocide" of Congolese Tutsis called the Banyamulenge.
"We cannot wait to be exterminated," he said, speaking from his base near Goma, north of Bukavu.
"We are going to solve it by means of a gun unless the government acts now. We are tired of waiting."
In June, he took Bukavu, saying he was saving Banyamulenge but he later withdrew, admitting there had been no genocide.
The UN is concerned about the threats of "retaliation" for the massacre, and the Security Council is due to discuss the region later on Thursday.
"We have limited means, of course, but we have deployed additional troops to the border area, we are continuing helicopter surveillance over the border area and we are patrolling Lake Tanganyika," said its spokesman Fred Eckhard.
In June, there were anti-UN riots across DR Congo, after its peacekeepers in Bukavu failed to stop Gen Nkunda seizing the town.
On Wednesday, a meeting of eight regional leaders declared the Burundi Hutu rebel National Liberation Forces (FNL) a "terrorist group" after it admitted responsibility for the massacre.
However, both Rwanda and Burundi say a coalition of anti-Tutsi groups from all three countries was involved.
The refugees - many of them women, children and babies - were shot or hacked to death with machetes.