Cause of fire at Swiss ski resort that killed 40 revealed as officials speak out

The cause of the fire that ripped through a bar in Switzerland on New Year's Eve has been confirmed.

At least 40 people are said to have died in the incident while more than 100 people were injured in the fire, including 19-year-old footballer Tahirys Dos Santos.

Four of the injured are in intensive care in a critical condition.

Of the 119 report injuries, 113 have been identified, BBC News reports. In regards to the fatalities, officials have warned of long identification waiting times.

Regional governor Mathias Reynard said: "We are painfully aware that identifying the bodies, as well as the injured, may still take a terribly long time for the families involved."

Elsewhere, police commander Frederic Gisler said that it is their 'priority' to name the deceased.

Pierre-Antoine Lengen, head of the Swiss Judicial Police, added: "No mistakes can be permitted. We need to give the correct remains back to the families."

Harrowing footage showed the moment the fire engulfed the establishment on what was supposed to be a night of fun and celebrations.

So far, two French bar managers have been interviewed as part of the ongoing investigation, says the BBC. Beatrice Pilloud, Valais attorney general, said that this has helped them establish who was at the venue when the fire broke out.

Initially, the authorities did not disclose how the fire started, but they always ruled out the possibility of it being an attack.

After further investigation it has now been determined that it was caused by sparklers that were in champagne bottles on the night in question.

These sparklers got too close to the ceiling of the bar and quickly set the whole venue on fire.

In videos and pictured shared online, people were seen holding up bottles of fizz with the sparklers inside of them.

A view of the scene after the several dozen people were killed in a bar in Switzerland (Muhammet Ikbal Arslan/Anadolu via Getty Images)

The blaze has been described as a 'flashover', meaning that it was a fire in an enclosed space that spread rapidly.

The president of the UK Association of Fire Investigators, Richard Hagger, says that this kind of fire can spread 'within a matter of seconds'.

"The room, in effect, becomes a full room on fire within a matter of seconds," he told the BBC of flashover fires.

If you have experienced a bereavement and would like to speak with someone in confidence, contact GrieveWell on (734) 975-0238, or email [email protected].

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