Searchers say there is virtually no hope the three crew members of a Norwegian yacht missing in freezing conditions in Antarctic are still alive.
Nothing has been seen or heard of the crew of 14-metre steel yacht Berserk since an emergency beacon was activated from the Ross Sea, about 33km from Scott Base on Tuesday afternoon.
HMNZS Wellington searched the area but called it off because of poor weather and rough seas.
The Sea Shepherd Conservation Society ship Steve Irwin joined the search and had its helicopter flying over the region for most of yesterday.
Skipper Paul Watson told NZPA chances of finding the crew alive were "pretty much zero".
He said conditions were so bad spray was freezing in the air as his ship ploughed into the heavy seas.
The missing yacht had a liferaft on board but it Mr Watson said whatever occurred must have been very fast.
"They didn't manually call or put out a distress signal. It was an automatic distress signal from an EPIRB (emergency beacon) that got detached and was activated by the water. Usually that doesn't happen unless the boat sinks or is turned over."
The yacht had dropped two crew members off on the ice to trek to the South Pole.
Mr Watson said the duo had given him a idea of Berserk's position but a search of about 90 per cent of the area had found nothing.
"If the vessel is floating we should have found it. All I can think of is that it got holed by ice and went down.
He said he had seen "pop up growler" icebergs.
"You don't even see them and they just pop up like a cork. They are solid blue ice and can do some serious damage."
The yacht had dropped two crew members off for a trek to the South Pole.
It is believed the yacht skipper, Jarle Andhoey, 34, may have been dropped on land and was not on the yacht.
Mr Watson told NZPA today they had searched about 90 per cent of the search area but had found no trace of the missing yacht.
He said the two crew members on land had given them a good position of where they yacht was.
"If the vessel is floating we should have found it. All I can think of is that it got holed by ice and went down. It is definitely not in McMurdo Sound and if it is, it is on the bottom."
Mr Watson said there was virtually no hope in such atrocious conditions.
Four of the crew were believed to be Norwegian and the fifth was English.