A bomb attack has killed at least 25 people and wounded 32 others in northern Nigeria's Zaria city, the state governor has said, BBC reports.
A suspected suicide bomber targeted civil servants at a government building in the city, witnesses said.
Emergency workers have rushed to the scene to help evacuate the wounded.
Militant Islamist group Boko Haram, which often targets northern Nigeria, has stepped up attacks since President Muhammudu Buhari took office in May.