Two mountain guides have died and climber Jo Morgan has survived after an avalanche hit near Aoraki / Mt Cook.
Police have now confirmed the two guides were from overseas.
Ms Morgan, a well-known adventurer, was with two professional mountain guides on Harper Saddle on Mt Hicks, near Aoraki / Mt Cook when they were caught in the avalanche.
The bodies of the two mountain guides have been removed from the scene, police said.
Area Commander Inspector Dave Gaskin said that while they were New Zealand residents, they were from overseas and they still needed to inform next of kin.
He said the two men were based in Central Otago and were well-known in the area. He said the tragedy will have a huge effect on the local community.
Ms Morgan, wife of entrepreneur Gareth Morgan, managed to free herself and is safe, they said.
READ MORE: Checkpoint's Lisa Owen speaks to Jo Morgan
Department of Conservation director-general Lou Sanson who was at Mt Cook Village this morning said Ms Morgan was "shattered" but lucky and very strong.
She had been "completely buried" in snow for about 30 minutes until she was able to activate her personal locator beacon and then took another 20 minutes to free herself.
"She's done a textbook recovery. She had one hand free to get snow out of her mouth and then release the PLB (personal locator beacon).
The avalanche came down about 5.30am and Ms Morgan was able to release the locator beacon about 6am.
"Time is absolutely critical. From that 6am response we were able to swing into action and to be on the mountain by 7.30am," Mr Sanson said.
"She described being able to put her arm up and feel air above her somewhere, she was getting cold and then she came to the surface and couldn't see her two companions."
She completely freed herself and sought help," Mr Sanson said.
Mr Sanson said all three climbers were all on one rope length when the avalanche hit. The group had left Empress Hut, the highest hut in the Southern Alps, that morning and had reached Harper Saddle.
Ms Morgan was flown by helicopter to Christchurch Hospital for treatment.
Mr Sanson was at Mt Cook Village to attend the funeral of DoC worker Scott Theobald who died in a helicopter crash near Wanaka on 18 October.
Mr Sanson praised the actions of DoC staff first on the scene as part of the Alpine Cliff Rescue team and helped recover the bodies of the two mountain guides, who were friends of many of his staff.
Two helicopters and two rescue teams were used in the search along with an avalanche dog and its trainer. Another helicopter from Christchurch was being prepared to go to the area with medical supplies.
Yesterday the New Zealand Avalanche Advisory issued alerts for dangerous conditions around Aoraki / Mt Cook and Mt Hutt until Friday.
It said there was "considerable risk" above 1400m on Aoraki / Mt Cook.
The warnings were for alpine areas with an increasing risk of storm slabs, and an alert was also in place for the Craigieburn Range until this afternoon.
The advisory said spring was usually one of the more active times of the year for avalanches.
Avalanche New Zealand director Andrew Hobman said if climbers were carrying an avalanche transceiver beacon, rescuers could locate them under the snow.
"[You then] use a long probe, which is a bit like a tent pole, to probe into the snow to finally locate them, and then you need to to dig them out."
He said there was not a lot of time to rescue someone under the snow.
"It's a medical emergency and teams are trained very well on getting there as quickly as possible and getting the people out of the snow as quickly as possible.