Donat Kibwana, a local official, accused the fighters of belonging to a rebel group.
Fighters stormed the village of Kokola in Beni territory on Monday evening, Kibwana said.
The rebel group known as the Allied Democratic Forces (ADF), originally from Uganda, has been operating along the DRC-Uganda border for more than 20 years, one of a number of armed factions active in the DRC’s east long after the official end of a 1998-2003 war.
“The mode of the attack was the same as that of the ADF,” Kibwana told Reuters news agency.
The attack came five days after the DRC’s army launched a large-scale operation against rebel groups, primarily targeting ADF fighters, in an area which is also fighting to contain the second-worst Ebola epidemic on record.
“While the army launched the large-scale operations deep into the forest, the rebels took the opportunity to attack the towns and civilians,” Kibwana added.
Several of ADF’s previous attacks have been claimed by the Islamic State of Iraq and the Levant (ISIL or ISIS) group, but the extent of their relationship remains unclear.
The ADF is not known to have pledged loyalty to ISIL.
Soldiers killed in clashes
Six DRC soldiers were also killed in clashes around Kokola on Monday night, according to sources cited by the Kivu Security Tracker (KST), a website that monitors violence in the region.
KST, which is a collaboration between New York University’s Congo Research Group and New York-based Human Rights Watch (HRW), said at least eight villagers were killed. The information could not be independently
The presence of the rebel group, along with a constellation of other fighters and armed criminal bands, has severely hampered efforts to contain the Ebola epidemic, which has infected more than 3,000 people and killed about 2,000 since August last year.
An estimated 160 rebel groups with a total of more than 20,000 fighters are still active in the DRC’s east.
The United Nations has tried to stabilise the country for the past 20 years with a 15,000-strong peacekeeping force.