A suicide blast in the northern Nigerian city of Kano has killed four people, police say.
They say that the blast happened in a street with many bars and night spots.
Witnesses say that the explosion was caused by a bomb in a car in the predominantly Christian area of Sabon Gari. The blast could be heard from several miles away.
The militant Islamist group Boko Haram has carried out attacks in Kano state and other areas of northern Nigeria.
“At about 22:00 (21:00 GMT), we heard an explosion and immediately mobilised to the scene where we discovered a suicide bomber… Five people, including the bomber, were killed,” Kano Police Commissioner Adelere Shinaba said.
He said that the victims were “three men and a girl of about 12”.
The BBC’s Will Ross in Nigeria says that Sunday’s blast was so powerful that all that remains of the car is its engine.
Kano is the largest city in the mainly Muslim north of Nigeria.
In January 2012, about 150 people died there in a series of co-ordinated attacks by Boko Haram.
The group is fighting to overthrow the Nigeria government and create an Islamic state.
The bombing comes as the Nigerian authorities continue the search for more than 200 schoolgirls kidnapped by Boko Haram.
The abducted schoolgirls, who include Christians and Muslims, were seized on 14 April in the north-east Nigerian town of Chibok in Borno state.
Boko Haram released a video last week showing more than 100 of the girls and offering an exchange for prisoners.
African leaders meeting in Paris at the weekend agreed to wage “war” on Boko Haram, pledging to share intelligence and co-ordinate action against the group.
French President Francois Hollande called Boko Haram a “major threat to West and Central Africa”, and said it had links with al-Qaeda’s North-African arm and “other terrorist organisations”.
The unrest in Nigeria has not just been confined to the north.
Earlier this month a car bomb in the capital Abuja killed at least 19 people and injured 60 more.
The explosion happened close to a bus station where at least 70 people died in a bomb blast on 14 April.