Nigerian police now confirm at least 21 people have died in a large explosion at the Banex Plaza shopping centre in the capital Abuja.

Another 17 people were injured in the blast, which tore through the centre in rush hour when it was packed with shoppers. Some 40 cars parked nearby were damaged or destroyed, and glassed shopfronts nearby were shattered.

The cause of the explosion has not yet been identified, but the radical Islamist group Boko Haram has hit the capital twice with bombs in the last month claiming a hundred lives.

Emergency services were quickly on the scene, which is now being fine-combed by explosive experts.

Boko Haram, which is trying to create an Islamic state in the north of Nigeria and captured international headlines recently by kidnapping 200 girls in a night raid on their school, is increasingly moving its operations further south out of its heartland.