Nigerian troops have killed 76 Boko Haram and Islamic State West Africa Province (ISWAP) militants in the country's northeastern Borno state in recent weeks, a spokesperson said on Thursday.

The militants were believed to belong to the armed group Boko Haram and its offshoot ISWAP, who have been waging a deadly insurgency in northeast Nigeria since 2009 that has displaced millions and killed thousands, with Borno at its epicentre.

The militants have stepped up attacks in Borno since the beginning of the year, including an assault on Dumba community on Sunday where at least 40 farmers were killed.

Military spokesperson Maj-Gen Edward Buba said troops killed 24 fighters during offensive operations in Damboa, Bama and Chibok areas of Borno between January 7 and 13.

He did not provide details on troop casualties during the operations.

Troops arrested 72 suspects and rescued eight hostages during the operations, he said in a statement.

Buba said weapons and ammunition, including AK-47 rifles, grenades, rocket-propelled grenades, and improvised explosive devices, were recovered during the operations.