Three mountaineers - the Icelandic John Snorri, the Pakistani Ali Sadpara and the Chilean Juan Pablo Mohr - are missing on K2 where they were attempting to climb to the summit.
Chang Dawa Sherpa who is at base camp reports via social media: "We haven't heard from them for more than 30 hours and their GPS trackers are off".
In the next few hours, a reconnaissance by helicopter by the Pakistani army is planned.
The Italian Tamara Lunger was also involved in the attempt and managed to descend to the advanced base camp.
During the descent, due to a fall, the Bulgarian Atanas Skatov lost his life.