Rescuers trying to reach a ship trapped by sea ice in Antarctica were themselves thwarted by thick "multi-layered" ice more than 6.5 feet deep. By Saturday morning local time, the Chinese ice-breaking ship was stopped after encountering the heavy ice and could not continue forward on its search and rescue mission, according to the Australian Maritime Safety Authority.
The 74 passengers aboard the stricken MV Akademik Shokalskiy have been trapped in the ice for four days and had hoped the Chinese ship sent to rescue them would arrive Friday.
But the Snow Dragon had its own progress delayed by the extreme Antarctic conditions and AMSA confirmed that the ship’s mission was at a halt in a post on its official Twitter page.
The agency also said AMSA’s Rescue Coordination Centre Australia was “considering all available options.” The third vessel, the Aurora Australis, is expected to arrive by Sunday evening.
Another icebreaker, a French-flagged ship, is no longer involved in the rescue, Reuters reported.
Expedition leader professor Chris Turney told NBC News on Friday the Snow Dragon had encountered "multi-layered ice, two-plus meters thick (6.5 feet)."
He had previously said his ship was in regular contact with Snow Dragon, which was "finding it heavy going" but "pushing on" through the difficult conditions.
Turney is head of the Australasia Antarctic Expedition. He chartered the ship for a mission to retrace the footsteps of Australian geologist Douglas Mawson, who explored the Antarctic 100 years ago. It left the port of Bluff, New Zealand on Dec. 8 where it is due to return in January.
Turney told NBC News that despite good morale on the ship, conditions had been challenging.
"When we first got stuck in the ice, we could see icebergs on the horizon, and that was disconcerting because you can only see 20 percent of them and they move not just in relation to the wind, but what the current is doing under the water," he said via satellite phone.
Earlier Friday Turney tweeted a picture of the Snow Dragon on the horizon.
"Great news," said Turney, who is a professor at the University of New South Wales, in Australia. "Icebreaker Snow Dragon on horizon with penguins! Everyone very happy!"
They had initially expected to be met by the ship two-to-three hours after seeing it on the horizon. But extreme conditions delayed this estimated time of arrival by another five hours.
The Australian Maritime Safety Authority spokeswoman Andrea Hayward-Maher told NBC News on Tuesday: "It is a very remote location so it is not your everyday search-and-rescue mission."
The ship is 100 nautical miles east of the French Antarctic base Dumont D’Urville. But all those aboard spent Christmas Day and the day after trapped inside the ice-locked ship.
Turney said the ice had enveloped the ship "very, very quickly."
"It's a classic misunderstanding, that this environment moves at glacial pace, and it's quite the reverse," he said.
The 233-foot-long Russian-flagged ship sent out a distress signal, which was picked up at 7:20 a.m. Australian Eastern Daylight Time (3:20 p.m. ET Tuesday) by the Falmouth Maritime Rescue Coordination Center, in the U.K.
As the ship is in the Australian search-and-rescue region, this message was passed on to AMSA, which alerted the Snow Dragon.
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