Kano - A suicide bomb on Wednesday in the northern city of Kaduna killed at least 25 people, in what appeared to be an assassination attempt on a cleric who has criticised Boko Haram, police said.
"We have recorded a blast which is apparently a suicide blast targeting the convoy of Sheikh Dahiru Bauchi," who escaped unhurt, Kaduna police chief Umar Shehu said. "Twenty-five people have so far been confirmed dead," he added.
The explosion went off at roughly 12:30pm (1130 GMT) as Bauchi's convoy was driving in an open-roofed truck, greeting well-wishers who had assembled for the closing of a prominent Koranic festival.
Bauchi, like most of Nigeria's prominent Muslim leaders, has publicly condemned Boko Haram's brutal five-year uprising aimed at creating a strict Islamic state in the north.
The insurgents have accused Nigeria's senior cleric of betraying the faith by submitting to the authority of a secular government, currently led by a devout Christian, President Goodluck Jonathan.
Boko Haram has claimed the killing of several clerics across the north, while assassination attempts targeting Nigeria's second and third most powerful Islamic leaders have both failed.
Kaduna, once the north's political capital, has seen relatively little Boko Haram violence in the last 12 months.
Suicide blasts targeting Kaduna churches in 2012, blamed on the militant group, sparked sectarian clashes in the religiously divided city that left hundreds dead.