Another hypothesis popularized by Donnie Eichar's 2013 book Dead Mountain is that wind going around Holatchahl Mountain created a Kármán vortex street, which can produce infrasound capable of inducing panic attacks in humans [REF].
Some people believe it was a military accident which was then covered up; there are records of parachute mines being tested by the Russian military in the area around the time the hikers were there.