Swiss authorities said Friday they are investigating whether sparkler-style “fountain” candles attached to champagne bottles ignited a deadly flashover inside a crowded basement bar here shortly after midnight on New Year’s Day, as videos circulating online show the venue previously parading flaming bottles through dense crowds.
The fire, one of the deadliest nightlife disasters in modern Swiss history, tore through Le Constellation during a holiday celebration and left about 40 people dead and at least 115 to 119 injured, many with critical burns and smoke inhalation. The attorney general in Valais canton said early findings point to decorative sparklers held too close to a low ceiling. Hospitals from Sion to Lausanne and Geneva declared surge conditions, and burn centers in neighboring countries accepted transfers. Flags flew at half-staff as families pressed for news and investigators sifted debris in a small Alpine town better known for World Cup ski races and winter tourism.
Witness accounts describe a routine champagne “presentation” on a packed dance floor moments before flames raced overhead. Patrons screamed and surged toward a narrow staircase to the street as the room filled with black smoke. Several people smashed windows for air; others crawled as heat descended. “It happened in seconds,” said a survivor who recalled grabbing a stranger’s hand near the bar and losing sight of friends at the stairwell. Emergency crews reached the scene within minutes, establishing triage on the sidewalk while firefighters attacked hotspots below ground. By sunrise, portable lights raked a cordoned entrance as helicopters ferried the most severely burned patients to regional centers.
Investigators said they will compare witness timelines, interior videos and social clips showing bottle-service sparklers inside the venue in the weeks before the disaster. The working hypothesis is that sparks or sustained flame contacted overhead materials, possibly decorative panels or insulation, triggering a rapid ceiling fire and flashover. Officials emphasized that the cause remains preliminary pending laboratory tests. Authorities have not identified a specific manufacturer or supplier for the sparklers and have not said whether pyrotechnic devices were permitted under the bar’s license. A criminal inquiry into potential negligence is underway, standard in a mass-casualty incident, with interviews of staff, promoters and nearby business owners.
Police and health officials said victims include Swiss residents and international visitors from France, Italy and several other European countries drawn to the resort for the holiday week. Identification is slow because of severe burns; teams are using dental records, DNA and fingerprints. The injured range largely from late teens to twenties, officials said, reflecting the bar’s youthful crowd. Local leaders opened a family reception center, and counselors and translators were assigned to assist relatives arriving from abroad. The government thanked neighboring countries for offering burn beds and air transport as Swiss units reached capacity.
Le Constellation sits off a commercial street near hotels and rental chalets in the heart of Crans-Montana. On busy nights, capacity reportedly reached into the hundreds. The bar is below street level with a narrow primary stairway; authorities are reviewing whether exit routes, door hardware and emergency lighting met code and functioned under load. Inspectors will also test wall and ceiling materials for flammability and examine whether acoustical foam or décor accelerated the blaze. Officials have not released a verified occupancy count for the night, nor said whether a secondary egress existed or was accessible amid the crush.
The videos now under scrutiny appear to show staff carrying champagne bottles crowned with bright, crackling sparklers through dense crowds and near the ceiling. Fire-safety specialists say such devices can emit showers of hot particles and open flame for scores of seconds, presenting hazards in low-clearance rooms, especially where combustible finishes or decorations are present. Investigators will trace procurement records for the sparklers and cross-check delivery dates and usage logs, if any exist. Prosecutors have not alleged arson, and officials said there is no indication of a deliberate attack.
Emergency response unfolded quickly across the resort. Dispatchers logged the first call around 1:30 a.m. Local fire brigades and medics staged in the main square, then rotated teams down to the stairwell. Crews ventilated the basement and used thermal imaging to locate hotspots while paramedics performed airway management and treated burns. A temporary morgue was established under police guard. By midmorning, investigators had flagged floor areas, photographed track marks up the stairs, and collected melted fragments of a device believed to be a sparkler. A perimeter remained through the day as engineers assessed the structure’s stability.
Crans-Montana, a resort that markets itself to international visitors, had been at high occupancy for the holiday week. The main street’s festive displays and gondola traffic gave way to cordons and satellite trucks as news spread. “We heard sirens and saw people stumble out covered in soot,” said a shopkeeper who opened early to provide water to responders. Bar staff at neighboring venues said they accounted for patrons, checked exits and closed early. By afternoon, small memorials of candles and flowers appeared along the sidewalk while a light snow fell and visitors refreshed their phones for updates.
Swiss cantons set building and fire-safety rules, and recent guidance has stressed fire-retardant décor, posted occupancy and clear egress, particularly for underground venues. Investigators will evaluate whether the bar’s layout, crowd density and emergency lighting contributed to a bottleneck at the stair. They will also review inspection records, any prior notices, and the role of private security in crowd management. Regulators are expected to compare this event to prior indoor pyrotechnics disasters abroad that ignited foam or fabric near ceilings, drawing lessons about clearances, enforcement and the risks of bottle-service theatrics in confined spaces.
Officials outlined next steps: forensic labs will analyze debris and residues; veterinarians’ burn labs are not involved, but chemistry panels will test for accelerants and match melted fragments to known sparkler compositions. Detectives plan to reconstruct a minute-by-minute timeline using point-of-sale data, key video clips and radio traffic. The attorney general’s office will decide on any charges following the technical report. Civil actions are likely to follow, with insurers and experts examining liability among the venue, suppliers and contractors. Authorities said the venue remains closed under police seal.
Families fanned out between hospitals and the reception center seeking updates. “We are waiting for names,” said a woman who arrived from Lyon with relatives of a missing 19-year-old. A local pastor organized an evening vigil on the square. At the resort’s gondola station, skiers filtered past as officers guided vehicles down a narrowed lane near the cordon. A taxi driver said he ferried guests who left behind coats and wallets in the panic and later returned looking stunned. Hotel staff on adjacent blocks set out water and tea in lobbies as the cold set in.
The bar fire comes at the start of peak winter season for the region, which is scheduled to host major Alpine events in the coming years. Tourism officials said they will review safety coordination across nightspots, including briefings for operators on decorations, pyrotechnics and occupancy control. Local leaders said the focus now is on the injured and on identifying the dead. National figures expressed condolences and pledged support as the investigation proceeds.
By Friday evening, officials said the death toll remained about 40 with more than 100 injured, several still in critical condition. The scene examination continues through the weekend, with a preliminary technical briefing expected early next week once laboratory screens and structural assessments are complete.
Author note: Last updated January 2, 2026.