Six people including two young children were “lucky to escape with their lives” when a fire broke out underneath a “death trap” block of makeshift flats.

Firefighters were called to Park Way, in Burnt Oak, where a blaze had started in a car wash below the accommodation just before 10pm on Wednesday.

By the time crews arrived, the flames had spread to a nearby garage and were about to engulf the upstairs of the building, which had been converted into living accommodation.

Six people sleeping in the converted offices, including two young children, saw smoke pouring up through the floor and managed to escape.

Firefighters said the incident would most likely have been fatal had the family been asleep at the time of the blaze.

More than 20 firefighters from Stanmore, Mill Hill, Hendon, and Harrow evacuated seven other people from nearby flats and spent more than one hour fighting the flames.

Safety officers called to the scene were horrified by the lack of safety measures at the makeshift home and immediately placed a prohibition notice on the building, preventing it from being used to sleep people.

The fire is believed to have started in the engine of one of several cars parked underneath the dangerous sleeping accommodation.

Two cars were destroyed in the blaze and the flats above suffered smoke damage but no-one was injured.

There were no smoke alarms in the building and the only escape route was blocked.  Fire inspectors also found there was no fire resistance between the building and the escape route, meaning the blaze could easily have spread, trapping the residents upstairs.

London Fire Brigade says it is taking action against the owners of the car wash and those responsible for the living quarters above.

Deputy Commissioner, Rita Dexter, said: “The accommodation was a potential death trap and the people living there were lucky not to have been killed by the fire. Had it broken out later when they were asleep we may well have been faced with several fatalities.

“There were barely any safety measures in place and it’s just sheer fortune that one of the residents noticed smoke coming through the floor and called 999.

“It’s tragic that people are being forced to live in such dangerous conditions by landlords who choose to ignore fire safety laws. If we find that people are putting lives at risk by blatantly ignoring them we will have no hesitation in prosecuting.”