Five Nigerian troops were killed and seven injured when a roadside bomb went off in northeastern Nigeria, an army colonel said.

The explosive detonated in a village just outside of Mubi, the second largest city in Adamawa state on Wednesday, according to the colonel, who requested anonymity because he was not authorized to speak to media. James Philip, a local militia's leader, said the bomb went off when a team of soldiers and hunters were conducting a routine patrol of the area.

Philip and the colonel said they suspect the terrorist group Boko Haram was behind the explosion.

More than 1,500 people have been killed in Boko Haram's five-year Islamic uprising ravaging across the country's northeast. The group continues to capture territory under a self-proclaimed Islamic caliphate.