A haunting new photo captured the moment lit sparklers attached to champagne bottles ignited the ceiling at the Le Constellation nightclub in Switzerland — as officials have now confirmed the flares were behind the horrific New Year’s Eve fire that left at least 40 dead and more than 100 seriously hurt.

“Some hypotheses can be confirmed,”  chief prosecutor Beatrice Pilloud told reporters Friday, according to CNN. “As things stand, everything points to the fire starting from sparklers or flares placed in champagne bottles that came too close to the ceiling, which very rapidly led to a flashover fire.”

The distressing photo, verified by the BBC, shows flames beginning to spread over the low ceiling as unsuspecting revelers waved their sparklers and bottles high in the air at the doomed nightclub, located at the Crans-Montana ski resort in the heart of the Swiss Alps.

Another image shows a woman in a crash helmet holding up lit bottles while being carried back on the shoulders of a masked man.

Witnesses who were in the club that night had previously said the sparklers were responsible for the deadly blaze, before officials confirmed it.

“It was firework candles inside a champagne bottle that caused the explosion. The entire ceiling of the bar caught fire,” one witness, who gave her name as Victoria, told French broadcaster BFMTV.

The flames spread quickly through the bar, which could hold up to 300 people, making it difficult to breathe around 1:30 a.m. Thursday morning.

The initial fire then triggered what firefighters refer to as a “flashover,” in which all the combustible material in a room ignites at once, causing multiple explosions, Swiss authorities said.

Eyewitness Bastien Frema, 20, described the horror to the Sun.

“People were screaming. I saw people with burnt clothing shredded, hanging off them,” she said. “People were yelling, trying to get help. We couldn’t do anything.”

One 18-year-old, who did not want to give his name, told the BBC he entered the bar during the fire to search for his little brother — who he later learned was not harmed.

“I saw people burning … I found people burning from head to foot, no clothes anymore,” he said.

Authorities are now working to identify the victims, many of whom are believed to be foreign tourists visiting the popular resort.

The burns suffered by the mostly young crowd were so severe that Swiss officials said it could take days before they identify all the victims.

Mathias Reynard, head of government of the canton of Valais, said experts were using dental and DNA samples.

The sparkers appeared to be a popular party gimmick of Le Constellation.

Promotional videos from last year showed waitresses weaving through the crowd with flaming champagne bottles held aloft and nearly brushing against the ceiling.