There was complete panic, everyone was screaming, the two French women, Emma and Albane, told the BFM television channel.
According to the two women, the fire broke out after the bar's wooden interior caught fire because a small firework had been inserted into empty champagne bottles. However, authorities have not yet determined the cause of the fire.
Swedish man Richard Nordin was at the Le Constellation bar just hours before the fire broke out.
It's terrible, he told Sveriges Radio.
Richard Nordin continued to talk about the young people who were waiting in line to get in.
I'm thinking above all of the young guys and girls who were queuing to get in. A young girl tried to convince the guard that her friend, who was probably a minor, would be allowed in. I hope they didn't get in, Richard Nordin told Sveriges Radio.
Dozens of people are believed to have died in the fire, and around a hundred are reported to have been injured, many of them seriously.
The bar Le Constellation is described as a popular spot for young people, centrally located in Crans-Montana. The place consists of two floors, with a staircase leading down from the upper floor to a basement room, the local newspaper Le Nouvelliste reports.
