A Kiwi father and son are missing and feared dead after an avalanche on K2, the second highest mountain in the world.
Marty Schmidt and his son Denali have been reported missing on 8,611m tall K2 - the highest point in the Karakoram Range which spans Pakistan, India and China.
Schmidt had been blogging his trek on the website of outdoor adventure equipment company Macpac.
The company posted a message today stating that Schmidt and his son had gone missing after reaching Camp Three, which sits at 7,400m.
All other climbers on K2 had retreated to Base Camp and abandoned their expeditions due to the avalanche risk, Macpac said.
It was believed a search was underway for the pair.
Sam Newton, from the New Zealand Alpine Club, said he understood 53-year-old Schmidt and 25-year-old Denali had been missing for two days.
"This latest report from K2 base camp, by Adrian Hayes and posted with the agreement of Base Camp Manager Chris Warner, seems to confirm our worst fears."
"They believe that Marty and his son Denali, were killed by an avalanche at Camp 3 on July 26 or 27."
More details would emerge in the next few days, Newton said.
"Right now, our thoughts are with the friends and family who have suffered a tremendous loss."
British mountaineer Adrian Hayes, who was climbing with Schmidt's expedition, said all of Camp Three had been wiped out by an avalanche.
"The deaths of a father and son is a tragedy in itself but compounded even further by the fact that Marty and Denali - who were great people that we all got to know very well in the close knit community of K2 Base Camp - were very well known, highly experienced and extremely strong mountaineers, the last people many would expect to be killed on a mountain."
Last year, Schmidt became the oldest New Zealander to climb to the top of Mt Everest at age 51.
In earlier blog posts, Schmidt had said he was looking forward to he and his son being the first father-son team to reach the K2 summit.
"Cutting away from the horizontal world to the vertical world has so much power and grace attached to it, that I love to journey this way many times of the year," Schmidt blogged.
"I have been doing this now for over 38 years... Can't see myself stopping anytime soon either."
Schmidt completed a climb of Everest last month, before heading to Pakistan where Denali met him to start their K2 expedition.They were accompanied by Schmidt's good friend and fellow climber Australian Chris Warner.
Last month, ten climbers were shot dead while attempting an ascent of K2 after their camp was stormed by a group of gunmen. Pakistani militant group Jundullah later took responsibility for the killings.
Since K2 was first conquered in 1954, about 280 people have succeeded in climbing it - with roughly one death for every three successful climbs.
- Fairfax Media