A Nigerian soldier (centre) walks, at the scene of an explosion in Abuja, Nigeria
Survivors say Boko Haram gunmen invaded a northeastern Nigerian town just 85 kilometers (53 miles) from Maiduguri city before dawn, killing many villagers and setting homes ablaze.
Residents of Damboa town called an AP reporter to say they were piling up corpses.
A spokesman for the Nigerian Vigilante Group says its civilian defense fighters are reporting that half the town of Damboa is burning.
The town has been besieged for two weeks, since Islamic extremists on July 4 attacked a new military base set up on its outskirts. The Defense Ministry had reported repelling that attack and killing at least 50 insurgents with six soldiers killed. But locals say soldiers were driven from the base and the extremists have twice ambushed military convoys trying to reach it in the past week.