Boko Haram fighters have ambushed and killed scores of Islamic State’s West Africa Province (ISWAP) members.
The latest battle is part of a renewed war of supremacy between the deadly sects.
A video obtained by PRNigeria showed Boko Haram fighters loyal to Buduma parading ISWAP rivals.
They were later slaughtered and dumped inside makeshift graves around Lake Chad.
The captors also burnt some ISWAP insurgents alive inside their gun trucks.
However, the Multinational Joint Task Force (MNJTF) on Wednesday eliminated more than 30 ISWAP fighters.
Troops also rescued dozens of women and children during an operation in Gamboru Ngala Local Government Area of Borno State.
The military recovered a number of gun trucks, motorcycles and sophisticated weapons.