Officials said a building storing fireworks in the largest market area of Lagos Island exploded, and the ensuing blaze spread to up to nine buildings.The blast reportedly shook windows in homes miles away and a thick cloud of smoke could be seen over the city.More than 30 people have been injured.An official from the National Emergency Management Agency (Nema) told AFP news agency that a charred body had been pulled out of the building where the fireworks detonated.The force of the initial blast was such that some residents reportedly mistook it for a bomb or a falling plane.Windows in nearby buildings were shattered and a neighbouring school was badly damaged.Thousands of people in the area gathered to watch, as the fire destroyed neighbouring buildings.Some were desperately searching the crowd for information on family members while the fire was burning and sporadic fireworks explosions could still be heard.