Four fire engines and around 25 firefighters were called to a fire at the rear of a shop on Varley Parade in Colindale.
A shed used as makeshift accommodation was badly destroyed by the blaze. Fourteen people were evacuated from the flats above the shop as a precaution. Thankfully there were no injuries.
The fire is believed to have been caused by materials placed too close to a portable heater.
The Brigade was called at 0318 and the fire was under control by 0449. Fire crews from Hendon, Mill Hill and Stanmore fire stations attended the incident.