Boko Haram terrorists dressed as soldiers killed more than 200 civilians in northeastern Nigeria this week.
Community leaders say residents of Gwoza in Borno state knew an attack was coming and pleaded with the military to send troops, but no one came to defend them.
"We all thought they were the soldiers that we earlier reported to that the insurgents might attack us," one community leader, who managed to escape the massacre, said.
Boko Haram has been seizing villages and large swaths of territory in the northeast. The al Qaeda-affiliated group wants to see Nigeria converted to an Islamic state.
So far, dozens of Christian communities and churches have been attacked by the group.
Meanwhile, Archbishop of Canterbury Justin Welby, who is on an African tour visiting the continent's Anglicans, is meeting with Nigerian President Goodluck Jonathan on Thursday.
Welby expressed his "personal pain and condolence about the ongoing terrorism" and prayed with the president, who is also a Christian.