Gatumba, Burundi ? Attackers with machetes and automatic weapons raided a U.N. refugee camp in western Burundi, shooting and hacking to death at least 180 men, women and children, U.N. officials said.

Burundian Hutu rebels claimed responsibility, insisting the camp for Congolese Tutsi refugees fleeing tribal fighting was a hide-out for Burundi army soldiers and Congolese tribal militiamen.

But most of the victims appeared to be women and children. On Saturday, their charred remains lay among the cooking utensils and the smoldering remnants of their former homes.

The attack late Friday resembled the killing during the 1994 genocide in Burundi’s neighbor Rwanda and raised fears of retaliatory violence that could undo peace efforts in Congo.

The camp, 12 miles from the Congolese border, sheltered ethnic Tutsi refugees, known as the Banyamulenge, who fled fighting in Congo’s troubled border province of South Kivu, U.N. officials visiting the camp said.

“People were sleeping when the attack happened,” Eliana Nabaa, spokeswoman of the U.N. mission in Congo said. “People were killed as they tried to escape.”

Isabelle Abric, spokeswoman for the U.N. mission in Burundi, said 159 people were killed and 101 were wounded during the attack in Gatumba. At least 30 of the wounded died in hospitals, she said.

Leaflets distributed before the raid warned refugees to leave the camp or face attacks by a coalition of Burundian, Rwandan and Congolese factions seeking “to fight the Tutsi colonization in the region,” survivors said.

The attackers spoke languages and dialects from the Congo, Rwanda and Burundi and were believed to have crossed into Burundi from Congo, witnesses said. They asked not to be named for fear of retribution.

Later Saturday, Burundian officials and aid workers moved the refugees to a nearby school where they will be protected by the army, said Louis Niyonzima, the local mayor.

A spokesman of the U.N. refugee agency said the attackers had raided a nearby army camp before attacking the refugees.

“These guys were armed with grenades, machetes, and automatic weapons. While the attack was going on, they were beating drums,” said Fernando del Mundo, a spokesman for the U.N. High Commissioner for Refugees in Geneva.