Nigeria's military said Wednesday it had killed the second-in-command of Islamist group Boko Haram while repelling an insurgent attack earlier this month.
A military statement said there had been a bounty of 25 million naira ($156,000, 117,000 euros) on the head of Momodu Bama, who went by the alias Abu Saad.
"During the Boko Haram terrorists' attack... on 4 August, 2013 (troops) killed Momodu Bama," a statement from spokesman Lieutenant Colonel Sagir Musa said.
He was killed in the town of Bama in northeastern Borno state, Boko Haram's traditional stronghold, it added.
The military had previously said that the August 4 clashes in the town were sparked by an attack on a police base, which saw 17 insurgents killed in gunbattles.
Bama "was the terrorists' operation officer and second-in-command to Abubakar Shekau", the Boko Haram chief who has been declared a global terrorist by the United States, Wednesday's statement added.
While Boko Haram's composition has typically been hard to unravel, a source familiar with the group's make-up confirmed Bama's status as Shekau's deputy.
Musa told journalists that "it took over a week to verify" Bama's identity.
The military has previously claimed the killing of senior Boko Haram commanders, but such reports have not coincided with a decline in violence and it was not clear if Bama's alleged death would have a significant impact on the insurgent group.
Boko Haram is believed to made up of various different factions.
Some analysts say Shekau and his inner circle lead the hardcore Islamist branch, which is committed to creating an Islamic state in northern Nigeria and has no interest in dialogue.
The reported killing comes amid a large military offensive launched in May aimed at crushing the insurgency.
The military has claimed huge successes against the Islamists in the three-month operation, describing them as being in disarray and on the run.
But a spate of brutal and deadly attacks in recent weeks has raised questions about the effectiveness of the military campaign.
Raids on a mosque and village at the weekend in the northeast left at least 59 people dead.
In a shock nighttime attack targeting children, Boko Haram gunmen stormed a secondary school in the farming village of Mamudo last month, killing 41 students and one teacher.
Some analysts say the military may have only succeeded so far in pushing the insurgents into more remote areas, where recent violence has occurred.
The insurgency has left some 3,600 people dead since 2009, including killings by the security forces, whose members have been accused of major abuses.
Nigeria, Africa's largest oil producer, has a population of about 160 million roughly divided between a mainly Muslim north and predominately Christian south.
Nigerian soldiers patrol near Maiduguri on June 5, 2013. Nigeria's military said it had killed the second-in-command of Islamist group Boko Haram while repelling an insurgent attack earlier this month.