Welcome to the NewsHour. Some 40 people are dead and more than 100 injured, many seriously, after a fire tore through a bar in the Swiss Mountain town of Kronz, Montana on New Year's just hours after midnight.

Authorities have ruled out a terror attack, but the cause of the fire is still under investigation as the Swiss face a devastating scene.

This was the scene outside the Constellation, where Swiss authorities say a massive blaze

broke out in a packed and popular ski resort bar just after 1.30 a.m. on New Year's Day.

There were people screaming, and then people lying on the ground, probably dead.

Many had gathered there to ring in the new year when the celebration turned suddenly to chaos.

I'm still in shock. I can't comprehend what happened. I saw people being resuscitated.

I saw people completely burned. I saw people dying.

Today, as investigators combed through the rubble, officials said it will take days to identify

all of the victims, and that it is still too early to determine the cause of the fire.

But officials say flames likely triggered a sudden backdrop explosion.

Eyewitnesses described a rush of people trying to escape a basement bar through a narrow

bottleneck at the top of a staircase.

The first stairs are pretty easy to get through since they're wide and all that.

But after that, there's a small door where everyone was pushing, and so we all fell.

We were piled on top of each other.

Some people were burning and some were dead next to us.

In the early morning hours, casualties quickly filled local hospitals,

and some of the injured had to be flown by helicopter or jet to other cities,

where doctors raced to stabilize the burn victims.

Those who were there described a desperate scene.

I saw people pushing each other, falling down the stairs, and a frenzy to escape.

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