CRANS-MONTANA, Switzerland: Sparkling candles placed in Champagne bottles ignited the fatal fire at a Swiss ski resort that killed 40 New Year's Eve revelers and injured 119 more, investigators said on January 2.

The candles came too close to the bar ceiling, crowded with people, many of whom watched as the flames spread, another report said. 

Authorities planned to look into whether sound-dampening material on the ceiling complied with regulations and whether the candles, which emit a stream of upward-shooting sparks, were permitted for use in the bar.

The blaze that ripped through the busy Le Constellation bar at the ski resort of Crans-Montana was one of the deadliest tragedies in Switzerland's history.

Officials said they would also explore whether the resort had other safety measures in place, such as fire extinguishers and escape routes. The attorney general for the Valais region warned of possible prosecutions if any criminal liability is found.

The severity of the burns made it hard to identify victims, forcing families to provide DNA samples. In some cases, wallets and identification documents were reduced to ash.

The mother of Arthur Brodard, 16, from the Swiss city of Lausanne, was frantic to find him. "I'm looking everywhere. The body of my son is somewhere," she told reporters. "I want to know, where is my child, and be by his side, wherever that may be — be it in the intensive care unit or the morgue."

Frédéric Gisler, police commander of the Valais region, said the injured included 71 people from Switzerland, 14 from France, and 11 from Italy, as well as citizens of Serbia, Bosnia-Herzegovina, Luxembourg, Belgium, Portugal, and Poland. The nationalities of 14 others were yet to be determined.

Axel Clavier, a 16-year-old from Paris, told The Associated Press that he felt he was suffocating inside the bar where moments before he had been ringing in the new year. He managed to escape by forcing open a window with a table. Two or three other friends were still missing. He said he did not see the fire begin but noticed servers arriving with Champagne bottles topped with burning sparklers.

A spontaneous memorial formed near the bar, with mourners leaving candles and flowers. Hundreds more gathered to pray for the victims at the nearby Church of Montana-Station.

On Instagram, one account was filled with photos of missing people, as friends and relatives appealed for information about their whereabouts.

Valais regional government head Mathias Reynard told RTS radio on January 2 that there were "many accounts of heroic actions" and strong solidarity at the moment of the tragedy. He praised emergency services for their work the following day but said that in the first minutes, it was citizens — predominantly young people — who saved lives through their courage.

Two women told French broadcaster BFMTV they were inside when they saw a male bartender lift a female colleague onto his shoulders as she held a lit candle in a bottle. They said the flames spread quickly, causing the wooden ceiling to collapse.

One woman described a surge of people desperately trying to escape the basement nightclub by rushing up a staircase and through a narrow door. Another witness told BFMTV that people smashed windows to get out, some badly injured, while panicked parents drove to the scene to find out whether their children were trapped inside.

Surrounded by snowy peaks and pine forests, with ski runs reaching about 3,000 meters (nearly 9,850 feet), Crans-Montana is a major international alpine skiing destination. It also hosts the European Masters each August.