Here is the dramatic moment an underground fuse-box burst into flames in the middle of the night.
Families in Furzehill Road, Borehamwood, were awoken by a firework like bang when the electrical sub-station exploded, at around 2am on Monday morning.
Singer songwriter Rob Finlay was at home watching a film with his parents when the flames erupted.
He said: “I heard a loud bang, like a firework, so we went out to see what was going on. I just could not believe it.”
Mr Finley's video, fittingly titled War of the Worlds, shows residents looking out the window at the horror that was unfolding below.
It took fire crews around 30 minutes to control the blaze using a dry powder.
Elizabeth Riding, who lives with her husband, Toby, 39, was startled when the bang, which she likens to the sound of a welding machine, woke her up.
The 24-year-old housewife said: “It was really terrifying and I felt very shaken up by it all. I usually sleep with ear plugs so was surprised the noise woke me up.
“My puppy was barking and I was trying to control her. You expect the worst when you hear a sound like that during the night – your brain is not able to take in heavy information when you have just woken up.
“I could hear constant crackly bangs. I looked out the window and saw a flickering light and my husband said he could see huge flames. The fire crews were fantastic and did a great job in reassuring us. They told us to close the windows because it was quite smoky outside.
“It was not until 4am that everything came to a halt and I found it really tough to get back to sleep after all the drama. I went to stay with my parents yesterday because we were left without power until around 3pm.
“I am so glad it is over now.”
There were no reports of any injuries and the electricity board are now investigating the situation.