Mount Everest (illustrative)
Mount Everest (illustrative)Thinkstock

Twelve Sherpa guides were killed and tens are missing, officials said, after a high-altitude avalanche hit Mount Everest in Nepal. 

A group of about 50 people, mostly Nepali Sherpas, were hit by the avalanche at more than 20,000 feet, Tilak Ram Pandey of the Nepalese Tourism Ministry's mountaineering department told CNN

Another Nepalese Tourism Ministry official, Krishna Lamsal, told The Guardian that guides had gone early in the morning to fix the ropes for hundreds of climbers when the avalanche hit them just below Camp 2 around 6:30 a.m. local time. 

So far, twelve have been recovered and rescuers have rescued eight Sherpas alive from the avalanche, according to the Himalayan Times. Five more Sherpas are unaccounted for and believed to be buried, officials said. 

Hundreds of climbers, their guides and support guides had gathered at the base camp, gearing up for attempts to scale the 8,850-meter (29,035 ft) peak early next month when weather conditions become more suited for the climb.