The Mai-Mai Mazembe militia perpetrated the violence against Hutus in and around the village of Kyaghala, a majority-Hutu area, Francis Bakundakabo, the local representative of the governor of North Kivu province, told AFP.
The Mai-Mai Mazembe militia, which killed 30 civilians in November, is made up of members of the Congo's Nande, Hunde and Kobo communities. It is only one of many such groups operating in the country, particularly in North and South Kivu provinces.
Twenty-four of the victims were killed with machetes and one woman shot dead, local civil society activist Hope Kubuya told AFP. Kubuya's group went to verify the attack.
"This raid by the Mai-Mai Mazembe in the Hutu village will inflame the inter-ethnic conflict in the region," he said.
Dozens of civilians have been killed in ethnic clashes in eastern Congo DRC over the past year. Conflict has never really died down in the region in the 20 years since hundreds of thousands of ethnic Hutus poured over the border from Rwanda, fleeing the genocide in that country.