CANBERRA, Australia (AP) -- An Australian icebreaker carrying 52 passengers who were retrieved from an icebound ship in the Antarctic resumed its journey home on Saturday, leaving behind another two icebreakers trapped in pack ice.
The Aurora Australis will continue its interrupted resupply mission to Australia's Antarctic base Casey Station before returning to the Australian island state of Tasmania in mid-January with the rescued scientists, journalists and tourists.
It had been slowly cracking through thick ice toward open water after a Chinese ship's helicopter on Thursday plucked the passengers from their stranded Russian research ship Akademik Shokalskiy and carried them to an ice floe near the Australian ship. But on Friday afternoon, the crew of the Chinese icebreaker Xue Long, or Snow Dragon, that had provided the helicopter said they were worried about their own ship's ability to move through the ice.
The Australian Maritime Safety Authority's Rescue Coordination Centre, which oversaw the rescue, told the Aurora to stay in the area in case help was needed. Under international conventions observed by most countries, ships' crews are obliged to take part in such rescues and the owners carry the costs.
The U.S. Coast Guard said Saturday that one of its cutters, the Polar Star, is responding to a Jan. 3 request from Australia, Russia and China to assist the two trapped ships. The Polar Star was cutting short its planned stop in Sydney, Australia, to assist the Russian and Chinese ships because they may not be able to free themselves from the ice.
"Our highest priority is safety of life at sea, which is why we are assisting in breaking a navigational path for both of these vessels." Vice Adm. Paul F. Zukunft, the Coast Guard Pacific Area Commander, said in a statement released by the Coast Guard after passengers had been successfully evacuated from the Russian ship. "We are always ready and duty bound to render assistance in one of the most remote and harsh environments on the face of the globe."
The Polar Star left its homeport of Seattle in early December to take part in one of its main missions, Operation Deep Freeze, to break a channel through the sea ice of McMurdo Sound to resupply and refuel the U.S. Antarctic Program's McMurdo Station on Ross Island. The Polar Star is the U.S. Coast Guard's only active heavy polar ice breaker.
On Saturday, AMSA said the Aurora was allowed to continue and that the Chinese ship was safe assistance.
Andrew Peacock, an Australian doctor and photographer who was rescued from the Russian ship, said his fellow passengers had been frustrated by the news Friday that their journey home had been delayed by another potential rescue operation.
"My feeling, and those of others I believe, today is one of relief at finally having a concrete plan for how and when we can return to loved ones, family and friends," Peacock said in an email from the Aurora.
The Chinese ship remained stuck several kilometers (miles) from the Russian icebreaker Akademik Shokalskiy, from which the passengers were rescued. The Russian ship has been immobile since Christmas Eve.
A reporter for China's official Xinhua News Agency who is aboard the Snow Dragon, Zhang Jiansong, said an iceberg appeared overnight and blocked the ship's return route. He said the ship would again try to find a way out, possibly as early as Monday.
Zhang said late Saturday that the 101 crew members on board the vessel were safe and had plenty of supplies.
An Antarctic tourism operator is holding out hope that the Russian icebreaker will be free in time to take 48 sightseers on a cruise of Antarctica's Ross Sea.
Heritage Expeditions has leased the Akademik Shokalskiy to depart New Zealand for the cruise on Jan. 17.
Heritage Expeditions general manager David Bowen said he would give the ship until Monday to break free from the pack ice before considering "other options."
The Aurora had offloaded only 70 percent of its cargo at Casey last month before it was diverted to the rescue.
It will now deliver the remaining 30 percent, which includes scientific equipment vital to research projects scheduled to be carried out during the narrow window of the Antarctic summer.
Australian Antarctic Division acting director Jason Mundy said the rescue had stretched resources for the summer research program, which he hoped to recoup from the Russian ship's insurer.
In addition to the disruption to Australia's scientific program, the rescue will cost Australian taxpayers 400,000 Australian dollars ($358,000), Environment Minister Greg Hunt's spokesman John O'Doherty said.
Associated Press writers Kristen Gelineau in Sydney and Didi Tang in Beijing contributed to this report.
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