Video footage has emerged of the aftermath of a major explosion that rocked a crowded shopping complex in the Nigerian capital Abuja.

The bomb blast at the Emab Plaza, in the upmarket Wuse 11 suburb, left 21 confirmed dead and 17 injured, according to national police. Local reports suggest that scores may have been killed in the attack.

In the video, released by Nigeria\'s Sahara TV, firefighters are seen battling a blaze among the twisted wrecks of several cars.

There have been no claims of responsibility for the attack, but Islamist group Boko Haram is believed to be behind the blast as it continues to wage an insurgency against President Jonathan Goodluck\'s administration.

Eyewitness Chiamaka Oham told the BBC: \"We heard a really loud noise and the building shook, and people started screaming and running out.

\"We saw the smoke and people covered in blood. It was just chaos.\"

The blast represents the third major attack in the capital in the last two months. Last month, a car bomb attack killed at least 19 people and injured more than 60 at a bus station in the city.

Boko Haram, who wish to create an Islamic caliphate within Nigeria, kidnapped more than 200 schoolgirls in April in the village of Chibok, bringing global attention to the west African nation\'s fight against terrorism.

The group\'s attacks have killed more than 2,000 people so far this year alone.