A suicide car bomber has killed five people on a street of popular bars and restaurants in the northern Nigerian city of Kano.

Police said the area is mostly inhabited by southern Christians.

Kano police spokesman Musa Majiya said the bomber struck Gold Coast Street in the Sabon Gari or "foreign quarter" of the morth's biggest city.

"I heard a loud blast. And there was a lot of smoke. Soldiers came in to cordon off the place and ambulances were rushing people to hospital," said witness Abdul Dafar.

There was no immediate claim of responsibility, but blame is likely to fall on violent Islamist group Boko Haram.

Its struggle against the Nigerian state has killed thousands over the past five years.

The blast comes as the Nigerian authorities continue the search for more than 200 schoolgirls kidnapped by Boko Haram, which has carried out numerous attacks in the same area in the past.

The militants also operate in neighbouring Niger, Cameroon and Chad, and Nigerian President Goodluck Jonathan described them as West Africa's al-Qaeda on Saturday in Paris.

Regional leaders were meeting French President Francois Hollande to discuss how to tackle the growing threat posed by the group.

Outrage over Boko Haram's kidnapping of the school girls has prompted Mr Jonathan, criticised at home for his government's slow response to the crisis, to accept US, British and French help in the hunt for the girls.

US officials have said the effort to retrieve the kidnapped girls is now a top priority.

However, it has been complicated by Nigeria's early reluctance to accept assistance and US rules banning aid to forces that commit human rights abuses.