Suspected Islamist extremists have killed 15 Christians by slitting their throats in an attack on a village in Nigeria's volatile northeast, residents and a relief source said on Sunday.

"From the information we gathered, the attackers broke into selected homes and slaughtered 15 people in their sleep," the relief official said on condition of anonymity because he was not authorised to speak publicly. Authorities had previously confirmed the Friday attack in Musari, but gave few details and said only five were killed.

AFP