The London Fire Brigade said 25 fire engines and roughly 150 firefighters were deployed to the scene on Bridge Road, where an official declared a major incident due to the suspected presence of fireworks and gas cylinders stored inside the building. Fire crews have been ordered to keep a safe distance and are now tackling the blaze remotely to protect staff.
A large section of the warehouse and commercial unit caught fire, and authorities warned of a prolonged operation due to the size and complexity of the site. Firefighters are expected to remain on scene throughout the day.
Three schools, a residential building, and surrounding properties were evacuated as a precaution. The cause of the fire is not yet known.