Looking for His glorious appearing! Titus 2:13

"From the information we gathered, the attackers broke into selected homes and slaughtered 15 people in their sleep," the anonymous relief official said.

Authorities had previously confirmed the predawn Friday attack in Musari, but gave few details and said only five were killed. Musari is located on the outskirts of Maiduguri, the base of Islamist extremist group Boko Haram.

Lieutenant Colonel Sagir Musa, spokesman for a military task force in the area, said on Sunday that he stood by the toll of five dead.

Authorities tend to under-report death tolls, however, and the relief official's information matched that of residents, who spoke of 15 people having their throats slit.

Residents said they suspected the attackers were from Boko Haram.