S Korea ferry: Desperate search for survivors continues
Distressing footage has emerged, apparently showing passengers waiting to be rescued, as Lucy Williamson reports
Emergency services are continuing to search for almost 300 people missing after a ferry carrying more than 460 people sank off South Korea.
Officials say 179 people have been rescued. Most of the passengers on board were students and teachers from the same high school on a field trip.
Emergency teams have been using floodlights and flares to search the vessel for survivors overnight.
At least six people are thought to have died, with dozens more injured.
The vessel was travelling from Incheon Port, in the north-west, to the southern resort island of Jeju.
The latest figures say 475 people were on board with 290 still unaccounted for.
It is not yet clear what caused the ship to list at a severe angle and flip over, leaving only a small part of its hull visible above water.
Rescue efforts are concentrated on the ship's wreckage, which sank in about 30m (98ft) of water. Many passengers are thought to be trapped inside.
Strong currents
One senior emergency official was quoted as saying it was unlikely the remaining passengers would be found alive.
"I'm afraid there's little chance for those trapped inside still to be alive," Cho Yang-Bok told YTN television, quoted by the AFP news agency.
But the country's Prime Minister, Chung Hong-won, said there was not "a minute or a second to waste" in the search for survivors, urging those involved to do their utmost to save more lives.
He had water thrown at him as he visited angry relatives gathered at the port of Jindo, near to where ferry capsized, according to the Associated Press.
Officials say the rescue operation involving coast guard, military and commercial vessels has been hampered by poor visibility and strong currents.
"There is so much mud in the sea water and the visibility is very low," said Lee Gyeong-og, vice-minister of security and public administration.
The US Navy has sent an amphibious assault ship, the USS Bonhomme Richard, to assist with the search and it is standing by to provide support as requested.
Navy divers have managed to enter three compartments of the ship but have not yet found any bodies.
Flares light up the early morning sky as teams continue to search the capsized ferry
Relatives wait anxiously for news of their loved ones at a port in Jindo
Parents at Danwon high school hold a candle light vigil in Ansan. More than 300 students from the school were on board the ship
A coast guard official told Reuters that divers were later prevented from entering the submerged ship for several hours due to strong tides.
Rain, strong winds and fog are forecast for Thursday, and may hamper further rescue efforts, the news agency adds.
'Shaking and tilting'
At least 325 of the passengers on board the ship were students from Danwon high school in Ansan, near the capital, Seoul. The students, aged 16 and 17, were heading on a field trip to Jeju island with about 15 teachers.
The ferry sent a distress call at around 09:00 local time (00:00 GMT) on Wednesday after it began to shake and take on water, about 20km (12 miles) off the island of Byungpoong.
Military and civilian ships and helicopters have been searching for survivors
Rescued passengers were taken to the nearby island of Jindo
Survivors say they heard a loud thud, before the boat began to shake and tilt.
Some of the passengers managed to jump into the ocean, wearing life jackets and swim to nearby rescue boats and commercial vessels.
One student told local media they were instructed not to move as it was dangerous.
"I am told that my friends and other friends could not escape as the passage was blocked. It seems that there are many students who could not get out as the passage was blocked by water," the unnamed student said.
Another passenger said the ship was "shaking and tilting", with people tripping and bumping into each other.
Among the confirmed dead was a female member of crew and a male high school student, who died after being rescued.
Local TV stations broadcast footage of the ferry listing and later sinking, within two hours of sending a distress signal.
Images showed rescue teams pulling teenagers from cabin windows, as some of their classmates jumped into the sea.
South Korean President Park Geun-hye has expressed sadness over the incident, saying it was "truly tragic" that students on a field trip were involved in "such an unfortunate accident".
Prime Minister Chung Hong-won had water thrown at him as he visited angry relatives gathered Jindo, according to the Associated Press.
Kim Young-boong, an official from the company which owns the ferry, has apologised.
"I would like to say sorry to the passengers, which include a number of students and their parents, and promise that our company will do its best to minimise loss of life. We are sorry," he said, according to the AP news agency.
"We will try to determine the cause of the accident after rescue operations are over," Lee Gyeong-og said.
As the disaster unfolded on Wednesday, there were conflicting accounts of the number of people rescued. Early reports suggested over 300 people had been plucked to safety but South Korean officials later revised this down.
The vessel - named Sewol - is reported to have a capacity of up to 900 people and is 146m (480ft) long.
Correspondents say this could turn out to be South Korea's biggest maritime disaster for more than 20 years.
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