A radical Islamist sect has claimed responsibility for a suicide car bombing at a north Nigeria church that killed at least 15 people.

In a statement sent to journalists Monday, a spokesman for the sect known as Boko Haram claimed Sunday's attack in the city of Bauchi, the capital of Bauchi state.

The statement also again threatened journalists in Nigeria over what the statement described biased stories about the sect's actions.

Sunday's bombing wounded dozens of people, as the car bomb detonated as worshippers left an early morning church service.

Boko Haram is waging an increasingly bloody sectarian fight with Nigeria's weak central government. The sect is blamed for killing more than 550 people this year alone, according to an Associated Press count.