The killings are the latest blamed on the rebels of the Allied Democratic Forces (ADF), who are accused of murdering more than 300 people in seven months of massacres in and around the major trading hub of Beni in DR Congo's North Kivu province.
The latest massacres occurred near the town of Mbau, not far from Beni, regional administrator Amisi Kalonda told AFP by telephone.
The Muslim rebels of the ADF, who launched an insurgency in neighbouring Uganda against President Yoweri Museveni in the mid-1990s, are accused of a series of killings in and around Beni that have left more than 300 people dead since October last year.
While a degree of calm was restored, the intervention failed to bring a halt to the killings of civilians.
