Armed men on Monday night attacked three locations in Barkinladi Local Government Area of Plateau State, killing about 40 people.
The Chairman of the Christian Association of Nigeria, CAN, in Plateau, Sonja Bewarang, on Tuesday officiated a mass burial of 15 of the corpses at Tatu area of the council on Tuesday.
Mr. Bewarang blamed security operatives for allowing the attack to occur.
Among the victims were pregnant women and children.
The tension in Barkinladi had been reported last week after some Fulani youth were allegedly killed by members of another ethnic group. The police had said they had stationed officers to prevent the breakdown of law and order in the area.
Hundreds of people have been killed in ethno-religious crisis in Plateau this year with the Special Task Force, a joint operation of all security agencies, unable to prevent the attacks from occurring.