More than seventy fire fighters worked for six hours to get a "challenging" industrial fire under control in east London.
Ten people had to be evacuated from neighbouring homes in London Road, Romford as there were cylinders inside one of the buildings.
Firefighers said these can sometimes explode when they get too hot so they had to be continually cooled.
The building was home to a range of industrial and commercial businesses including a glass manufactures and a gym.
Firefighters were called just before 2am on Sunday and are expected to remain on the scene for some time due to the nature of the fire.
The cause of the fire is under investigation.