The Allied Democratic Forces (ADF), a partly Islamist armed group of Ugandan origin, is accused of carrying out the brutal slayings, the latest of which took place overnight August 13-14 and left 51 people dead.
Lieutenant Mak Hazukay, an army spokesman in North Kivu province, told AFP that late yesterday the ADF had entered the town of Kiteya - about 20 kilometres (12 miles) north of the city of Beni.
The region around Beni has been the target of a series of massacres that have claimed more than 700 lives since 2014.
The Congolese government has blamed the mass murders on the ADF, but a report published in March by the Congo Research Group at New York University, which probed these massacres, claimed that soldiers from the regular army had also participated in the killings.