EDITOR’S NOTE: This story contains descriptions and video that readers may find disturbing.
As young revelers rang in the New Year in a packed bar in the Swiss Alps, the celebration quickly turned into a nightmare when a devastating fire swept through the basement, killing at least 40 people and injuring 119 others.
The fire at Le Constellation in Crans-Montana has been described by the president of Switzerland as one of the country’s “worst tragedies”. As families anxiously await word on missing loved ones and experts work to identify victims, authorities are still piecing together how the fire started and why it spread so quickly.
Swiss authorities said Friday that champagne sparklers were the likely cause of the fire, although the official inquiry is still ongoing. Emerging videos and eyewitness accounts show a deadly mix of dangers: fire-prone ceiling panels and a crowded bar packed with young patrons heading for a narrow escape route.
A night of celebration
Le Constellation, located in the heart of Crans-Montana, a luxury sky resort in the French and German speaking canton of Valais, is a popular nightspot among young locals and visitors.
Around 200 people were inside the venue on New Year’s Eve, according to eyewitnesses, ready to celebrate 2026 with music, drinks and dancing.
Sparkles that became smoke
Widely shared images online of show staff with motorcycle helmets perched on others’ shoulders, holding bottles of champagne with sparklers among the packed crowd.
One clip shows at least six bottles raised in the air as flames and smoke billow from the roof.
An image shared on social media shows what appears to be a waiter holding bottles of champagne with sparklers attached to them. Part of this image has been blurred by CNN to protect identities. – From social media
Another image shows the roof on fire. Part of this image has been blurred by CNN to protect identities. – From social media
It appears that the sparklers have connected what experts believe to be acoustic panels on the ceiling, a material designed to improve sound but which can also catch fire.
Independent fire consultant Stephen MacKenzie described it as “plastic petrol,” adding: “That’s why we’re seeing reports of so many young people with first, second, third and unfortunately, fourth degree burns.”
Swiss chief prosecutor Beatrice Pilloud told reporters on Friday that investigators are looking into the installation of foam panels in the bar, and whether it complied with the regulations.
A rapidly spreading fire
Once the fire started, it spread quickly.
One video shows a young man trying to put out the fire by hitting it with a cloth, while others record on their mobile phones or continue dancing, seemingly unaware of the impending danger.
“Once the ceiling was on fire, within about 10 seconds the entire nightclub was on fire,” said one witness.
Horrible escape
As smoke filled the hall and the fire burned, the party goers ran towards a narrow staircase.
Video verified by CNN shows dozens trapped at the exit, with one person jumping from a window as thick, red smoke engulfed the building.
MacKenzie explained the rapid spread of fire through a process called flashover, in which almost everything in a room catches fire at almost the same time.
“The combustions rise to the roof level,” causing the fire to “spread laterally,” he said. This process is like a “stone drop in an ocean,” with the smoke coming out the side and beginning to “preheat” everything in front of it.
When the fire door was opened it could have created a “chimney effect” that accelerated the upward flow of smoke and combustible gases, MacKenzie said. “The smoke is actually on the fire – a ‘flashover,'” he added.
On Friday afternoon Pilloud, the Swiss prosecutor, said that all the signs support that theory: “As things stand, everything indicates that the fire started from sparklers or firecrackers placed in champagne bottles that came too close to the ceiling, which very quickly led to a flashover fire.”
Le Constellation was split into at least two levels, with a staircase leading to a basement level as seen in a photo posted by the bar’s management on TripAdvisor in August 2016. – By Le Constellation
Laetitia Place, a 17-year-old from Lausanne, recounted her painful escape from the fire, and said that there was a crush in the narrow exit that made it difficult for others to pass.
“The first stairs are quite easy to pass because they are wide and all that. But after that, there is the small door where everyone was pushing, so we all fell, we were piled on top of each other, some people were burning, and some were dead next to us,” the young man told Reuters.
Video obtained by CNN shows multiple people lying outside motionless, while bystanders try to help.
Local resident Samuel Rapp, 21 years old, saw the consequences.
“There were people screaming, and then people lying on the ground, probably dead. They had jackets on their faces – well, that’s what I saw, nothing else. Then I received videos where people were trying to get out, but they were throwing themselves on top of each other, so it was difficult to get out of the exit. And there were people screaming, saying ‘help me,’ please.
Emergency services arrive
The Swiss emergency services launched a response within minutes of the fire, transporting the injured to hospitals across Switzerland and abroad. About 50 patients have been or will be transferred to hospitals in other European countries for specialized care, authorities told reporters on Friday.
The aftermath of a fire at a ski resort in Crans-Montana, Switzerland, can be seen in this screengrab from a police video on Jaunary 1. – Police Cantonale Valaisanne
Edmund Coquette told CNN-affiliate RTL Germany that he saw “bodies in the streets,” and young people “totally burned in the face,” who were missing fingers.
Dr. Robert Larribau, head of emergency care at Geneva University Hospital, told CNN that most of the patients were between 15 and 30 years old, many with “extremely serious injuries” caused by flashover and possible backdraft.
Flashover typically causes severe burns, particularly on the face, back and upper limbs, often accompanied by critical breathing injuries from radiant heat and superheated gases. Backdraft, an oxygen-driven explosion, can cause instantaneous fatal burns and toxic inhalation.
An investigation has been launched into the circumstances surrounding the fire and how it spread so quickly, as Swiss officials said on Friday that the two French owners of the bar had been interviewed by police.
CNN reached out to the bar owners through their businesses but has yet to receive a response.
Meanwhile, until Friday evening, many loved ones of the victims and injured were still waiting for answers, and the authorities continue with the process to identify the dead.
CNN’s Martin Goillandeau, Billy Stockwell, Henrik Petterson, Nic Robertson, Joseph Ataman and Duarte Mendonca contributed reporting.
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