Kano - Four people were killed, including a young girl, in a suicide car bomb attack in Kano on Sunday, the city's police commissioner said.
"At about 2200 (2100 GMT), we heard an explosion and immediately mobilised to the scene where we discovered a suicide bomber... five people, including the bomber, were killed," said Adelere Shinaba.
The victims were "three men and a girl of about 12", he told reporters at the scene of the blast in Sabon Giri, a predominantly Christian district of the city.
But he added that it was too early to say who was responsible.
An AFP reporter said the charred and mangled remains of five cars could be seen outside one of the many bars and eateries on the now deserted street, which was dimly lit because of power cuts.
A sixth car, a Volkswagen Golf said by police to have been used by the bomber, was ripped into three pieces, with its engine resting on the roadside.
Windows on the two-storey buildings lining the street were smashed and armed police and soldiers stood guard.
The blast, which happened when the area was crowded with revellers as well as street hawkers and traders, could be heard several kilometres (miles) away, locals said.
Witnesses had earlier claimed that a car was left in the Middle Road area of the neighbourhood and its driver left on a motorbike. The blast happened soon afterwards.
Links were made on social networking sites to the vote but the explosion also came a day after Nigeria and its neighbours announced a regional response to the threat by Boko Haram.
Themilitant group has been holding 223 of 276 girls it kidnapped from a school in the town of Chibok, in Borno state, on April 14, which has led to an international response to find them.
Cameroon's President Paul Biya said at a meeting of regional leaders in Paris on Saturday that they had gathered to "declare war" on the extremists, whose five-year insurgency in northern Nigeria has claimed thousands of lives.
Boko Haram has been blamed for attacks across the border in Cameroon and on the eve of the French summit, 10 Chinese construction workers were kidnapped during a raid on their camp in the north of the country.
Sabon Giri has also been attacked before. At least four strong explosions rocked the area on July 29 last year, killing 12. Outdoor bars appeared to be the target.
The military at the time blamed the attack on suspected Boko Haram members.
The attacks shattered a lull in insurgent attacks in the city, which has previously seen heavy violence blamed on the militants.
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