Sherpas load mountaineering equipments used for climbing on yaks after Mount Everest expeditions were cancelled in Solukhumbu district April 27, 2014. There was fury among the roughly 400 sherpas at base camp after the April 18 accident on the perilous Khumbu icefall, the single deadliest disaster on the world's highest mountain. Chanting, pumping their fists and threatening violence, a group of young sherpas forced an expedition boycott that now looks almost certain, for the first time, to write off a whole season for hundreds of would-be summiteers. The sherpa backlash, which had simmered for years as a cut-throat business expanded, could deal a blow to the commercial expedition industry that took off in the mid-1990s - pushing costs for climbers even higher. To match Insight NEPAL-EVEREST/ REUTERS/Phurba Tenjing Sherpa(NEPAL - Tags: TRAVEL SPORT BUSINESS)