Attempts to find a small plane carrying three Canadians on an Antarctica trip, which disappeared on Wednesday, have been delayed because of bad weather.
The Twin Otter aircraft was on a routine supply trip between bases when it lost contact with the ground and disappeared over a mountain range.
A rescue plane circled the area where the plane disappeared but could not find it due to high winds and heavy cloud cover, the Rescue Co-ordination Centre New Zealand said.
Rescue co-ordinator John Ashby said a DC-3 Dakota aircraft circled the area for five hours but could find no sign of the missing plane amid 105mph winds, solid cloud cover and heavy snow.
"The forecast for the next 12 hours is for similar conditions, but if there is a break in the weather the joint New Zealand and US field rescue team is ready to go from McMurdo Base at short notice," he said, as the search was suspended overnight.
RCCNZ said the search involving fixed wing aircraft and helicopters was concentrating on a rugged area midway between the South Pole and Terra Nova, which lie about 870 miles apart.
RCCNZ spokesman Steve Rendle said there were hopes the three men, whose names have not been released, were still alive.
"If the beacon is operating, which it is, that's a good sign as a heavy landing can tend to prevent the beacon working, so that's a positive sign at this stage," he told Radio New Zealand.
The plane was equipped with survival equipment, including mountain tents, and supplies sufficient for five days, RCCNZ added.
Antarctica has no permanent residents, but several thousand people live there in the Southern Hemisphere summer as a number of countries send scientists and other staff to research stations.
The US runs the largest programme, with about 850 staff at its McMurdo Station and another 200 at its Amundsen-Scott South Pole Station, where the Canadians' flight originated.