At least five people were killed and eight were injured Sunday in a bomb attack on a Catholic church in a mainly Christian area of Kano, the largest city in Nigeria's north, police said.
The attack came shortly after the end of mass at the Saint Charles Catholic church, police spokesman Frank Mba told AFP.
"We suspect an IED (improvised explosive device) that was thrown from across the road" at the church in Kano's Sabon Gari district, which has suffered previous attacks by the Islamist group Boko Haram, he added.
Also in Kano on Sunday, a woman suicide bomber blew herself up outside a university after police prevented her from carrying out an attack, injuring five officers, Mba said.
"A female suicide bomber was isolated as she was walking towards the gate of the university," Mba said, adding that she had hidden the bomb under her "long black hijab".
"Police on duty isolated her" because she was behaving strangely, Mba said.
They were about to ask a female colleague to frisk the woman when she detonated the bomb, killing herself and injuring the five police officers, he said.
Police also said they had made safe a remote-controlled car bomb near a mosque and the home of a prominent Kano sheikh on Saturday.
"The police were alerted by some vigilant residents last night," said Kano police spokesman Musa Magaji Majia. "Our bomb disposal personnel succeeded in defusing the IED."
While Boko Haram, which is seeking to install an extremist Islamic state in Nigeria, has killed dozens during a recent spate of strikes in the far northeast, Kano has also seen two attacks in recent months.
On June 23, a bomb blast at a public health college in the city killed at least eight, while on May 19, a suicide car bomb attack in Sabon Gari killed at least four people, including a young girl.
At least four strong explosions rocked the same area on July 29 last year, killing 12.
Blame has been attributed to the Islamist militants, whose violent insurgency began in the mainly Muslim north in 2009.