I've panicked badly while staying in a fairly remote bit of Scotland in a tent by myself - middle of the night some large animal blundered onto my tent, made a lot of noise and scared the wits out of me. I was camped in a narrow bit of ground between a steep mountainside and the sea at the head of a sea loch (fjord) - to show you how irrational I was I thought it was a bear even though there haven't been bears in Scotland for over a thousand years!

Felt pretty silly when I noticed a large herd of deer not far away the next day.

I suspect having more people with me would have made us react even more irrationally. I'm a pretty experienced hiker and generally fairly level headed....

My brother and I were once camping on the Tour du Mt Blanc. As we were washing up after eating in the dark, we saw multiple sets of approaching eyes reflecting our one headlamp. Wolves? We couldn't tell. They seemed very large and intimidating, whatever they were and weren't a familiar form even as they got closer.

We became increasingly nervous until it turned out that we'd camped on the wrong side of a fence and curious horses were approaching our campsite in their paddock. Probably didn't help that I had a childhood fear and recurring nightmares about horses. Later, we woke up to them licking the tent.

I woke up once to what I thought was the sound of Velcro outside my tent. I called out to my cousin (his backpack was leaning against the tree next to my tent) that it is too early and I was trying to sleep.

Unzipped the tent and took a look out. The sound was a bear ripping my cousin's backpack open. He did not leave any food inside, but had let some food touch the pack and left a scent.

I quickly closed the tent and let the rest of the group run the bear off.

I don't think I could camp anywhere that had bears!

Since the requirement in the US for the use of bear canisters (plastic cylinders that bears cannot open) for food storage the problem has gotten a lot better. Bears used to be more aggressive once they learned that people have food. Now in general they have learned that the food cannot be accessed and tend to stay away; though some have learned that if you scare the people when the canister is open they can get the food out.

@Cerium I'm not aware of any such requirement per se, mostly just that it's good advice. We used to tie our food up but you have to pick the right tree or the bear will simply climb up the tree or pull the tree over to bring the food within reach.

The regulations are not national, but enforced by individual park services. As far as I'm aware all national parks with bears require proper food storage. Many states have regulations as well. A quick search shows that parks in New York with bears require their use during the summer.

What odds would you give for it happening to experienced hikers? One in a million? Then it'll happen with some frequency.

It's a common argument with these things that the proposed explanation is improbable. I don't get it. We are looking at something improbable (otherwise it wouldn't be interesting in the first place), the question is just figuring out which improbable thing it is.

Yes, the question is the mystery. That's why it's interesting, because it has to be one of a few improbable options.

"Something" convincing 9 experienced outdoorsman to slice open their tent (why not open the door?) and flee is a pretty crazy story. Add the other things that don't easily fit a plausible explanation, and it's really interesting.

Here's my plausible explanation:

The hikers are awoken by some disturbance. They discuss among themselves briefly, and decide to go out--a few people start putting on shoes, while someone is attempting to open the tent door. Something spooks them, and they all panic and want out now. A convenient knife to the wall provides a faster exit point, and they run out and make for shelter of trees.

I have some experience hiking and backpacking, but the information given in the Wikipedia article is way too sparse for me to attempt to derive a coherent explanation. For example, there's no indication of where the clothing was located for those who were undressed; more importantly, there's insufficient explanation to posit when the group broke into the two who stayed at the tree, the three who tried to return, and the four who died in the ravine.

A sound suggesting an approaching avalanche could lead to the panic you mention. Plus, someone further up mentions the possibility of the tent door being frozen or difficult to open.

I think it's suggested that some might have taken clothes from those that froze to death, explaining those left naked. If some climbed trees and fell, or fell into a ravine, that could explain most of the injuries.

Experienced hikers, but still human beings sleeping in the dark. It wouldn't be normal or expected on a given night, but group panics do happen in such environments.