Switzerland will hold five days of mourning after an “unprecedented” fire tore through a crowded bar, killing about 40 people and injuring 115 who were celebrating at a New Year’s Eve party in the Alpine ski resort of Crans Montana.

The country’s president, Guy Parmelin, described the blaze as one of the most traumatic events in Switzerland’s history. “It was a drama of an unknown scale,” he said, paying tribute to the many “young lives that were lost and interrupted”.

Switzerland owed it to those young people, who had their “projects, hopes and dreams” cut short, to ensure such a tragedy never happened again, added the president.

Witnesses said the fire broke out at 1.30am in the town’s Le Constellation bar after sparklers or flares were put into champagne bottles. Two women told the French broadcaster BFMTV a bartender carried a female member of staff who was holding one of the bottles.
The flames set fire to the ceiling. 

Within seconds the blaze had spread, engulfing a crowded basement packed with revellers. Many were teenagers. One of the women described a crowd surge as people desperately tried to escape up a narrow flight of stairs.

Two people hug in foreground of the picture, as investigators walk past the screened-off building
‘It happened in seconds’: sudden inferno brings horror to Swiss ski 

Ulysse Brozzo, 16, an instructor at a local ski school, said several of his friends were in the club at the time.

He said he had spoken to some who were safe, but had yet to hear from others he knew were inside when the fire broke out. A friend of a friend was in a coma at Sion hospital. “It’s a total tragedy,” he said. “There were hundreds of people inside.”

Video posted by survivors showed the blaze taking hold immediately above the bar. Other footage showed grim scenes of orange flames billowing from a ground-floor lounge and several people lying motionless on the street.

The canton prosecutor for Valais, Beatrice Pilloud, said she could not comment on reports that lighted candles had caused the inferno. “An investigation is taking place. It will identify the exact circumstances of what happened,” she said, confirming that the basement steps were very narrow. She said it was too early to draw any conclusions about emergency exits.