The latest brutal attack comes on civilians in their homes and fields, violently killing 36. Dozens of angry protestors came out to the streets, chanting anti-government slogans and demanding protection.
Officials said suspected rebels killed 36 civilians in the northeastern part of Democratic Republic of Congo in a late Saturday night armed attack. The killings are said to be the deadliest one this year.
"The assailants hacked to death 22 men and 14 women late on Saturday in their homes and fields on the outskirts of the local commercial hub of Beni," governor of the conflict-ridden North Kivu Julien Paluku said in a statement.
He said: "The population of Beni has once again been hit by terrorist acts of diverse origins whose objective is to sabotage the efforts at peace undertaken over the last two years."
Local activists say more than 500 civilians have been killed near Beni since October 2014, most in overnight raids by rebels that carried out their attacks with machetes and hatchets.
Local army spokesman Mak Hazukay told Reuters that the attack was staged in the early evening by rebels from the Allied Democratic Forces (ADF), a Ugandan militia group that has operated in eastern Congo since the 1990s.
"We have just found their bodies."
The victims were found in the Rwangoma neighbourhood on the outskirts of Beni, Hazukay said, adding: "The search for the bodies continues."
He also said that ADF rebels had "bypassed" army positions "to come and massacre the population in revenge" for military operations in the area.
But the group ADF did not comment on the latest armed attack.
However, a United Nations panel of experts and independent analysts says that other armed groups, including some Congolese soldiers, have also been involved in attacks on civilians.
It appeared to be the deadliest attack in the area since an assault blamed on the ADF in November 2014 killed some 80 people.
Omar Kavota, the executive director at the Centre of Study for the Promotion of Peace, Democracy and Human Rights that documents violence in North Kivu, said he had received reports of as many as 50 dead.
Gilbert Kambale, a local civil society leader, said the attack took place between 7:00pm and 11:00pm (local time) on Saturday evening and that there were "already 35 bodies" in the morgue at Beni hospital.
The latest bloodshed provoked an angry protest, bringing around a hundred people onto the streets shouting anti-government slogans and demanding security.
The slaughter took place three days after DR Congo's President Joseph Kabila visited the region, promising to do everything in his power to bring peace and security.
Beni lies in North Kivu, a province that has seen a long spate of attacks that the government and United Nations blame on the ADF.