The bizarre incident at Dyatlov Pass

The bizarre incident at Dyatlov Pass

How did they die?
On February 2, 1959, a group of nine ski hikers entered the Ural Mountains in northern Russia. None of them returned, and the story told by their remains is still considered a bizarre mystery.
 
The group, led by a man named Igor Dyatlov, were young college students heading out towards a mountain about six miles from where they died. It was a difficult route at that time of year, but all of the party members were experienced in mountain expeditions, high altitude, and cold weather conditions.
 
The day before they died, the group was moving through a mountain pass (now named Dyatlov Pass) when a snowstorm hit. They deflected their route up the side of one of the mountains. When they realized they were heading in the wrong direction, Dyatlov made the call to pitch camp where they were and wait for the storm to clear.
 
They hunkered down on the side of a mountain whose name is variously translated as either "Mountain of the Dead" (meaning spirits) or "Dead Mountain" (meaning that it had no game). 
 
It took nearly a month before search and rescue teams were able to reach their remains. What they found was shocking.
 
The group's tent had been torn open from inside. The tent was empty, with all of their belongings scattered around on the snow. The group's bodies were found, mostly naked, having wandered a long distance through the snow away from the campsite.
 
Two of the bodies were found huddled beside the remains of a fire. They were dressed only in their underwear. The branches on the trees above them had been broken up to 15 feet above the ground.
 
Three more bodies were found scattered in the clearing, all naked. The remaining four were found in a nearby 13-foot ravine, still wearing most of their clothes.
 
Of the four bodies found in the ravine, three had severe internal injuries, which the medical examiner stated were from an extremely high force, comparable to a car crash. None of them showed any external sign of injury. The medical examiner said it was as if they had been crushed under high pressure. 
 
And one of the three injured bodies was missing its tongue.
 
Furthermore, all eight bodies were found to be incredibly radioactive.
 
There were no signs of struggle, and no footprints aside from those made by the eight hikers. Although "paradoxical undressing" is a classic sign of hypothermia, what would have lured these eight experienced mountaineers out of their tent in such a dramatic fashion? Why would they have succumbed to hypothermia in the first place, given that they were clearly well-versed in its signs? And where did their clothes go?
 
There have been many theories as to what happened, including an avalanche, secret Soviet military maneuvers, and UFO activity. But we will probably never know for sure.