The Congolese army on Thursday displayed 23 corpses it said were the bodies of militants killed in combat in the east, where the Islamic State also claimed an attack on the military.
The military showed the bodies in Beni, where hundreds of civilians have been killed since 2014 in attacks blamed on a shadowy Islamist force called Allied Democratic Forces or ADF.
The army said the militants were ADF fighters killed in fighting when they launched an attack on an army base.
"Early this morning, the ADF attacked our position in the town of Ngite-Mavivi, our men reacted and inflicted a heavy loss in their ranks," Congolese army spokesman, Major General Leon-Richard Kasong told AFP.
The ADF, forced out of Uganda in the mid 1990s, is frequently accused by DRC authorities of attacking army positions in North Kivu province.
But later on Thursday, the Islamic State's Central Africa affiliate also claimed an attack against the army "close the village of Mavivi in Beni area," according to the SITE jihadist monitoring group.
AFP was unable to immediately verify the IS claim. It was unclear what relation there is between the two Islamist militant groups in the north DR Congo.
Last month, the IS group for the first time claimed to be behind an attack on a Congolese army position in North Kivu province.
Islamic State-affiliated groups are operating in several central and West African countries, including parts of the Sahel and Nigeria, Chad and Niger.