Suspected Islamist militants attacked a Nigerian army base and captured soldiers and ammunition during a raid in the insurgency-hit northeastern Borno state in the early hours of Monday, two security sources told Reuters.

A surge in attacks this year by Boko Haram and its splinter rival Islamic State West Africa Province (ISWAP) has raised fears of a major comeback by jihadists, whose tactics include armed drones and explosive devices planted on major roads.

A soldier who escaped the attack said the militants arrived on motorbikes and gun trucks and laid siege on the 153 Task Force Battalion base in Borno's Marte district from around 0200 GMT.

The Nigerian troops retreated to the larger 24 Task Force Brigade in nearby Dikwa district where they regrouped and launched a counter-attack that retook the base, said the soldier, who declined to be named for security reasons.

Several soldiers were feared dead and others missing.

"As I'm speaking to you now, they killed many of our soldiers while some were captured alive by the insurgents while we were withdrawing from the attack," the soldier said.

Nigerian Army spokesperson Lieutenant Colonel Onyechi Appolonia Anele referred questions to the country's Defence Headquarters, which did not immediately respond.

A member of the Civilian Joint Task Force (CJTF), which is helping the military fight jihadists, said the militants took ammunition and burned the army's anti-mine resistance vehicles.

The CJTF member, who also escaped, said the military was still searching for the missing soldiers and had yet to account for the number of dead troops.

Security experts have attributed the resurgence to a lull in fighting between Boko Haram and Islamic State-backed ISWAP and the adoption of aerial technology by the groups.

Reuters