This fire department has a blunt message for people filming at emergencies

Whenever a fire breaks out, the odds are there will be footage posted on social media almost immediately.

But now the London Fire Brigade is urging people to think before they start filming.

"We're urging people to #Call999BeforeYouFilm," they wrote in a recent tweet. "If you see no fire engines at the scene, never assume someone else has called the emergency services. Any delay in calling 999 could have devastating consequences."

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“We attended a fire at a restaurant in Curzon Street in Mayfair last November and when we arrived, the fire was racing up the side of the building. I was astounded by the number of people standing there with their phones out taking photos and videos," said station manager Paul Askew.

“I asked several people if they had called 999 and they all said they had assumed someone else had. The fire was very visible yet we only received 15 calls, which is less than we would expect for a visible fire. Never make the assumption that someone else has called the emergency services. Your call could be the first and make a huge difference to the outcome of the incident.”

A recent Fire Facts report on incident response times found that 40 percent of domestic fatal fires were the result of a 10 minute-plus delay in calling 999.

The decision to call the emergency services first, before you hit record, could quite literally save lives.