Twin blasts kill dozens in Nigerian city

Dozens of people were killed in two bomb attacks in the northern Nigerian city of Kaduna on Wednesday, according to police and humanitarian workers.

The first attack — in which 25 are believed to have died — was apparently targeting a cleric critical of Boko Haram, the feared armed group that has deliberately targeted civilians in an increasingly bloody campaign. 

Thousands were gathered for prayers with Sheik Dahiru Bauchi in Murtala Muhammed square. When his convoy pulled up, the bomber lunged at him before being stopped by his private security, witnesses and police commissioner Shehu Umar Ambursa said. The cleric is believed to have escaped a previous attempt on his life earlier this Ramadan.

Another blast reported shortly afterward saw at least 14 people confirmed killed when a device exploded in the city’s crowded Kawo, according to police. That attack was apparently targeting opposition leader and ex-president Muhammadu Buhari.

A bomber in a car full of explosives hurtled towards Buhari's convoy at the crowded Kawo market, his son told Reuters on the scene and police confirmed later. 

Buhari later said in a statement that it was "mass murder" and "clearly an assassination attempt" and that "when I came out of my car I saw many dead bodies littered around."

Some reports indicated the death toll in the second attack was a far higher total of 50.

There was no immediate claim of responsibility, but Boko Haram has been staging attacks, especially with explosives, outside its northeastern heartlands in the past three months.

The group has often attacked Muslim leaders and imams who criticize its hard-line ideology.

Boko Haram, which is fighting to carve out an Islamist state in northern Nigeria, killed more than 2,000 civilians during the first half of this year, Human Rights Watch estimated last week.

The group sacked the northeast town of Damboa and surrounding villages over the weekend, killing at least 50 people.

Kaduna's governor Mukhtar Yero declared a 24-hour curfew on the city until further notice and condemned the bombs as "the height of cowardice."

"The enemies of peace have visited us with their ungodly venom of wanton destruction," he said in a statement. "Those behind the act have no notion of God, as they have none for the sanctity of human life."

President Goodluck Jonathan in a statement called it "an odious attempt to inflame passions and exacerbate disquiet, fear, insecurity and sectional divisions in the country."

The five-year-old insurgency has been in the international spotlight since Boko Haram fighters kidnapped more than 200 girls from a school in the northeastern village of Chibok in April. Jonathan met parents of the abducted girls for the first time on Tuesday.

Al Jazeera and wire services. Rawya Rageh contributed to this report.