Militants kill15 soldiers and four militia fighters after attacking their convoy in northeastern Borno state, security sources say. Meanwhile, search continues for dozens of students kidnapped in northwestern Kaduna state.
Daesh-aligned militants have ambushed a Nigerian military convoy, killing 15 soldiers and four militia fighters in the northeastern state of Borno.
"We lost 15 soldiers and four civilian JTF (militia) in the militants' ambush in the forest near Gudumbali," in the Lake Chad region, a military officer, who asked not to be identified, told AFP news agency on Saturday.
The attack that took place on Thursday and was reported two day later was the latest in a militant conflict which has killed 36,000 people and displaced hundreds of thousands in northeast Nigeria since it began more than a decade ago.
The military officer said 13 government fighters, including 10 troops, were wounded in the heavy attack carried by Islamic State West Africa Province (ISWAP).
The 10-vehicle convoy was on its way to Gudumbali from the town of Kukawa for a military operation against the militants when it came under fire, said another military source, who gave the same toll.
"The casualties were brought to Maiduguri this afternoon," the source told AFP, referring to the regional capital.
READ MORE: Nigeria steps up efforts to rescue dozens of kidnapped students
Army works with local militia
Militia leader Umar Ari said a vigilante leader in the area was among those killed.
Nigeria's army works with local militia forces as part of its battle against militants.
"Four of our comrades were among the dead, including, Yusuf Baba-Idris, the head of Civilian JTF in Kukawa," Ari said.
On Saturday, ISWAP issued a statement, claiming responsibility for the ambush, according to the SITE militant monitoring agency.
The group said its ambush "led to killing 33 elements and wounding nearly 20 others and taking one of them prisoner, while the survivors fled."
The group said its militants also destroyed military vehicles, captured more and seized weapons and ammunition.
READ MORE: Bandits carry out another deadly attack on village in northwestern Nigeria
Search for kidnapped students
President Muhammadu Buhari has come under increasing pressure to deal with Nigeria's security challenges, including the militant uprising, herder-farmer clashes as well as banditry and mass kidnappings in the northwest.
Nigerian security forces on Saturday were seeking to rescue dozens of students who were kidnapped in northwestern Kaduna state in the latest attack on a school.
Gunmen stormed the Federal College of Forestry Mechanisation in Mando at the outskirts of the state capital, Kaduna city, late Thursday and took more than 30 students away while the military rescued 180 after a battle.
Kidnap gangs are largely driven by ransom payments and have no known ideological leanings. Victims are often released shortly after negotiations.
READ MORE: Armed bandits hit northwest Nigeria in two separate deadly attacks
Rise of ISWAP
ISWAP split from the militant group Boko Haram in 2016, and has since become a dominant threat in Nigeria, attacking troops and bases while killing and kidnapping passengers at bogus checkpoints.
On March 1, militants burnt down a United Nations humanitarian compound in the town of Dikwa after dislodging troops, killing six civilians.
Nigeria's militant violence has spread to neighbouring Chad, Cameroon and Niger, prompting a regional military coalition to fight the insurgents.
READ MORE: Nigeria's mass kidnappings: A timeline