Nigerian troops killed four senior commanders of the Boko Haram splinter group ISWAP, including a member of its Shura Council and two high-ranking Arab fighters, during an operation in Borno State in the country’s northeast, the military said.

The operation took place late in the evening on Oct. 31 in the Kukawa Local Government Area after insurgents launched an attack on military positions, according to a statement issued Sunday by Captain Mohammed Goni, acting media information officer of Operation Hadin Kai.

The military identified the dead commanders as Abu Hajara, a prominent member of ISWAP’s Shura Council, and Abul Walid, a senior commander described as a close associate of the group’s overall leader, Ba Shuwa.

Two other high-ranking terrorists and several additional insurgents were also killed during the engagement, the statement said.

Troops, supported by air assets, repelled the assault and recovered weapons, ammunition and communication devices, according to the military.

The operation came three days after another military engagement in Buni Yadi where Nigerian troops killed 55 insurgents, including several commanders.

The military described the successive operations as part of efforts to weaken ISWAP’s leadership and disrupt its operational networks in northeastern Nigeria.

ISWAP emerged from a split within Boko Haram in 2016 and has become a major insurgent force in the Lake Chad Basin, operating across parts of Nigeria and neighboring countries.

The insurgency in northeastern Nigeria, which began in 2009, has killed thousands of people and displaced millions while disrupting livelihoods and humanitarian operations across the region.