A single photograph captured the moment the ceiling of a Swiss ski resort bar was ignited by young revellers holding up champagne bottles topped with sparklers.
The New Year's Eve celebrations were still in full swing as the flames quickly spread through the foam insulation above the partygoers' heads.
Around 200 young people were crammed inside the basement of Le Constellation bar in the luxury resort of Crans-Montana when the blaze broke out at 1.30am, tearing along the ceiling within seconds.
At least 40 people were killed and 115 injured.
Only one of the victims has been named so far – Emanuele Galeppini, a 16-year-old Italian golfer. Authorities have said it will take days to identify the rest because of the severity of their burns.
Many of the victims are believed to have been trapped in the bar's basement level, witnesses said, with reports suggesting that there were not enough emergency exits.
A crowd, largely aged between 15 and 20, rushed to escape up a narrow flight of stairs through a single door. Others tried to smash windows to escape as the fire started spreading to the ground floor.
Credit: via X
Police are investigating whether the bar, which videos show was densely packed, had exceeded the legal limit on the number of customers. Videos showed young people desperately trying to flee the bar as the flames engulfed it.
The footage, which The Telegraph is choosing not to publish, shows the party-goers trapped inside a room full of fire and smoke as the exit is blocked by a large crowd of people.
Screams and shouts can be heard as people try to push through the masses. The staircase to the snow-covered ground is blocked with injured people, coughing and struggling to move.
Emma, a French witness, said the fire had spread "in seconds", telling the French news channel BFMTV: "Some of the bottles were near the ceiling and it caught fire. The whole ceiling was in flames and the fire spread really fast. It happened in seconds. We all ran outside, screaming and crying.
"I saw a young man writhing in agony on the floor. His body and his hair were badly burned and half of his face had gone. I think he must have died."
Parents raced to the scene from around the town and beyond, trying to find out whether their children were trapped inside.
But they will have an unbearable wait to find out their fate.
Police said it would take "several days" to identify all of the victims owing to the burns and injuries being so severe. Many of the injured are young and in a serious condition, they said.
The resort town of Crans-Montana, 25 miles north of the Matterhorn mountain and around 150 miles from Zurich, is popular with tourists from Britain and elsewhere, who go there for the skiing and the party atmosphere.
Described by some as the "best place to celebrate New Year's Eve" in the town, Le Constellation was packed with young people, witnesses said.
"The party was in full swing ... music and champagne flowing freely," according to one witness.
Lighting sparklers in bottles in the cramped confines of the basement had featured in a promotional video for the venue posted on social media.
It showed waitresses wearing crash helmets walking through the club, waving pyrotechnics flaring out of Dom Perignon champagne bottles precariously close to the beamed ceiling.
Credit: YouTube / Constellation Crans Montana
Another witness, called Albane, said she saw the ceiling catch fire after the firework was lit in the bottle. "It was clearly accidental," she added.
The blaze likely triggered the release of combustible gases that ignited violently and caused what English-speaking firefighters call a flashover fire or backdraught.
One young man watching from across the street said he saw about 20 people scrambling to escape the smoke and flames.
'A horror movie'
Likening what he had witnessed to "a horror movie", he told The Telegraph: "We are broken. Apparently there were sparklers. They should be banned."
"How did this happen? I heard screaming after. People ran out everywhere, and then fire engines came."
Another witness told how he broke into the burning building fearing that his brother was trapped inside.
"We heard a big explosion and after that we saw a lot of smoke," he said. "I thought that my little brother was inside so I came and I tried to break the window to help people to exit."
Speaking to BBC News, the man said that once he managed to get inside, he saw people "burning from head to foot, no clothes any more", adding: "It was very shocking."
The man tried to help where he could, offering water and clothes to the injured, including giving his jacket to a man with burn injuries.
"It's very disturbing because I went in this bar every day in the week... just the day I don't go, it burned," he said.
Axel Clavier, a 16-year-old from Paris who survived the blaze, described "total chaos" inside the bar. One of his friends died and "two or three" were missing, he said.
He said he had not seen the fire start, but did see waitresses arrive with champagne bottles with sparklers.
Mr Clavier said he felt like he was suffocating and initially hid behind a table, then ran upstairs and tried to use a table to break a window. It fell out of its casing, allowing him to escape.
He lost his jacket, shoes, phone and bank card while fleeing, but said "I am still alive and it's just stuff".
Referring to the sparkler the witnesses said caused the fire, a bus driver told The Telegraph: "They're banned in a lot of clubs and they should never be allowed anywhere near crowded places. This is an absolute tragedy."
Crans-Montana's local authority had banned fireworks and sparklers during the New Year's Eve celebrations over concerns that a lack of rain over the past month had left conditions dangerously dry, increasing the risk of fires catching and spreading quickly.
A local reported hearing loud explosions coming from the vicinity of Le Constellation.
"I heard a number of massive bangs, which sounded like bombs going off. It was crazy," they said. "I live hundreds of yards from the bar. I heard screaming and screaming and people running."
Adrien, a witness who was outside the bar when the fire broke out, described the horror of watching those inside flee for their lives. He said: "There was a young man with burns on the pavement outside who kept saying: 'It hurts, I'm in pain, please call an ambulance.'"
Helicopters and ambulances went to the scene, with emergency services from neighbouring areas deployed to assist the rescue operation.
The intensive care unit and operating theatre at the regional hospital were overwhelmed with victims. Those suffering the worst burns were sent to university hospitals across Switzerland.
Credit: TikTok / ladzdrie92i
With the scale of the tragedy quickly becoming apparent, the authorities called on residents to show caution over the coming days in order to avoid placing further strain on the medical system.
One devastated resident arrived at the scene and broke down in tears.
He left floral tributes with the initials of local victims he knew and said the bar had been too crowded for him to enter.
He told The Telegraph: "I had friends at the club. I left the flowers there for my friends and all the others. My heart is bleeding.
"We almost went into Le Constellation, there were just too many people in the club. Had we not gone home we would have definitely got caught up in it.
"I had two friends who were in the club at the time… it could take another week to know. Inside is just unrecognisable… everything is charred.
"The fire happened in the underground and the fire came from the bottom and went to the main floor and then to the second floor. The glass was strong and people struggled to break through the glass.
"I woke up this morning and received over 50 messages from my friends and then I called other friends and some just aren't answering," he said.
Investigators have said they were working on establishing whether fire safety standards had been followed at the bar.
Le Consellation had received a poor safety rating online. One review platform awarded it just 6.5 out of 10 points in the safety category.
Swiss officials have been questioned by media about the state of the emergency exits but declined to comment, saying it was "too early to draw any conclusions".
Le Constellation is owned by a French couple, who have not been named but according to reports are a 49-year-old man and a 40-year-old woman who are said to be in shock.
The woman was present when the fire broke out and suffered burns to her arm. The pair had been living in the Rhône Valley, which Crans-Montana is located above, for around a decade, according to CNN.
Michela Ris, the deputy mayor of the Swiss town of Ascona, who was in Crans-Montana to celebrate New Year's Eve, described how she was frantically searching for friends on New Year's morning.
"Some acquaintances told me about young people leaving the bar covered in blood, some without their clothes. It was a real bloodbath," she told Swiss media.
"We have friends who are not responding to messages. Maybe they are just asleep, but we don't know if, after being at our house, they went straight home or if they went for one last drink, perhaps to the very club where the tragedy took place.
"We are very worried and are trying to contact everyone, one by one, to make sure they are ok. We are devastated."
Around 50 family members were waiting for news of missing loved ones.
As morning broke, residents and commuters gathered outside the building, many in tears, devastated at the night's events in their town.
Two 16-year-olds from Milan were among those injured, according to Italian news agencies.
One girl is still in a coma at a hospital in Zurich, while another teenager is being flown by helicopter to Niguarda Hospital in Milan with severe burns to his hand and head.
As the region declared a period of mourning, Mathias Rénard, head of the regional government, told reporters: "This evening should have been a moment of celebration and coming together – but it turned into a nightmare."
Guy Parmelin, the Swiss president, called the fire "one of the worst tragedies our country has ever experienced".
He said many emergency staff had been "confronted by scenes of indescribable violence and distress".
"This Thursday must be the time of prayer, unity and dignity," he said. "Switzerland is a strong country not because it is sheltered from drama, but because it knows how to face them with courage and a spirit of mutual help."
Emmanuel Macron, the French president, spoke with Mr Parmelin on Thursday and said the death toll was "devastating". "Our thoughts are with the families," he added.
A Foreign Office spokesman on Friday said: "Our thoughts are with all those injured and killed in the terrible tragedy in Crans-Montana, and we pay tribute to the Swiss emergency services who are leading the response. We will continue to monitor the situation, and our consular staff stand ready to support any British nationals who may be affected."
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