U.N. peacekeepers are scrambling to avoid new bloodshed in the volatile border area shared by Burundi, Rwanda and Congo following last week's massacre of Congolese refugees in western Burundi, the United Nations said on Wednesday. "We are concerned about public statements by leading officials and military personnel in the area about a possible intention to retaliate for the massacre," U.N. chief spokesman Fred Eckhard said. "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," he said. Jean-Marie Guehenno, U.N. undersecretary-general for peacekeeping, has briefed Secretary-General Kofi Annan, traveling in Geneva, by phone on the situation in the troubled Central African zone -- known as the Great Lakes area -- and plans to brief the 15-nation Security Council on Thursday, Eckhard said. The extremist Hutu rebel group, the Forces for National Liberation, claimed responsibility for last Friday's attack on a camp near Burundi's border with the Democratic Republic of Congo in which more than 160 Tutsi Congolese refugees were hacked, shot and burnt to death. --more 2140 Local Time 1840 GMT