27 Soldiers Killed in Attack

On Friday, troops launched a ground offensive on a stronghold of Islamic State-affiliated militants in a wasteland straddling Borno and Yobe states.

"The suicide attack killed 27 soldiers, including the commander, and left several others seriously injured," a military officer said, making this one of the deadliest suicide attacks targeting soldiers in recent years.

In July last year, seven troops were killed when their vehicle hit a landmine in a village where ISWAP is active.

The 15-year-old conflict has killed 40,000 and displaced around two million from their homes in the northeast.

The violence spilled into neighbouring Niger, Chad and Cameroon, leading to the creation of a regional force to fight the militants.