“Vitaliy Gorelik died in the base camp,” Sakhi Hassan, a mountaineer said.

The 15 climbers had been on the mountain, the world’s second highest, since late December and were hoping to make a summit push in mid-March.

Naiknam Karim said one of the climbers died Monday in base camp from breathing difficulties.

He says the team was waiting for better weather before being flown from base camp by helicopter.

Winter ascents of the world’s 14 highest mountains are some of the most prized achievements left in climbing.

K2 sees winter temperatures of 50 below zero and winds of up to 70 kilometers an hour (40 miles per hour) in winter.