Three veteran mountaineers were almost killed on Mount Everest this weekend, but not by the thin air or crippling cold that tried to do them in—it was a mob angry of Sherpas. The three European men were involved in a brawl at 24,000 feet when a dispute over climbing procedure turned into a violent, near-death scuffle that raises new questions about the overcrowding of the summit. Local officials are investigating the matter and say it's the first time they ever heard of such an incident at the world's biggest mountain.

The whole thing apparently began when a group of Sherpa guides instructed the three climbers not to touch the ropes that the guides were placing on the way to the summit. Traditionally, it's the local Sherpas who lay the groundwork for other climbers, by setting out the path to top and securing climbing lines. Witnesses say the three Europeans—one Italian, one British, and one Swiss climber—ignored the request and started climbing above them on their own. One of them may have also knocked some ice loose, hitting one of the Sherpas. 

The Europeans saw it differently, saying one of the Sherpas rappelled down on top of the Swiss climber, "who raised his hands above his head to protect himself. This prompted the lead climber to accuse Ueli Steck of 'touching him.'" The Sherpa then reportedly turned on the climber, swinging his ice axe in anger and threatening to hurt other climbers as well.

When the climbers all returned to base camp, a gang of around 100 Sherpas reportedly pelted the foreigners' tents with rocks, forcing them outside, where the locals attempted to beat and kick them. The men say that if another group of Westerners hadn't intervened to break up the fight, they might have been killed. 

The Tourism Ministry called it a "slight misunderstanding" that may have been blamed by language barriers. More likely, this is a spillover of frustration from overcrowding on the mountain that has started to overwhelm Everest each spring. The peak of Mount Everest is only accessible to climbers for a few weeks each year and April and May are the height of climbing season, when hundreds of mountaineers (of varying skill and experience) descend on Nepal to conquer the highest summit on the planet. But the extreme popularity of Everest tours—there are at least 32 expeditions this year—has the made scene almost unmanageable.

That also makes it more dangerousFour people died on the mountain last year, a tragic toll that many blamed on "traffic jams" that slow climbers down and force them spend more time than they should in the dangerous altitudes. Dealing with so many foreign climbers has also become a strain on the Sherpas, who are responsible for getting all the climbers to the summit and back alive. More than 4,000 climbers have scaled "the top of the world" since the Sir Edmund Hilary and his Sherpa guide Tenzing Norgay first did it in 1953. At least 220 have died trying.

Meetings between the Europeans and the Nepalese have reportedly smoothed things over for now, but unless the bigger problem of overcrowding is somehow relieved, more trouble in could be in store in the future.