GIGLIO, Italy (Reuters) - A South Korean honeymoon couple were plucked from a capsized Italian liner on Sunday, more than 24 hours after it was wrecked, and rescue workers were struggling to save another person trapped on board.

Teams were painstakingly checking thousands of rooms on theCosta Concordia for nearly 40 people still missing after the huge vessel foundered and keeled over with more than 4,000 on board, killing at least three people and injuring 70.

The task is akin to searching a small town - but one tilted on its side, and largely in darkness and submerged in freezing water. Scores of divers were taking part.

Just after dawn on Sunday, a team made voice contact with a third survivor still on board the ship. "We are doing the impossible to reach this person," coastguard spokesman Luciano Nicastro told Italian television.

After midnight, rescue workers had found the two South Koreans still alive in a cabin, after locating them from several decks above, and brought them ashore, looking dazed but unharmed.

The captain of the luxury 114,500-tonne ship, Francesco Schettino, was under arrest and accused of multiple manslaughter, causing a shipwreck and abandoning ship, Italian police said.

Passengers, comparing the disaster to the movie "Titanic," told of people leaping into the sea and fighting over lifejackets in panic when the ship hit a rock and ran aground near the island of Giglio, late on Friday.

Two French tourists and a Peruvian crew member were dead and 38 people were unaccounted for.

The vast hulk of the 290-metre-long cruise ship, resting half-submerged on its side, loomed over the little port of Giglio, a picturesque island in a maritime nature reserve off the Tuscan coast. A large gash was visible on its side.

Rescue workers including specialist diving teams were working their way through more than 2,000 cabins on the ship, a floating resort that boasted a huge spa, seven restaurants, bars, cinemas and discotheques.

As the search continued, there were demands for explanations of why the vessel had come so close to the shore and bitter complaints about how long it took to evacuate the terrified passengers after the ship ran aground late on Friday.

State prosecutor Francesco Verusio said investigations might go beyond the captain.

"We are investigating the possible responsibility of other people who could be responsible for such a dangerous maneuver," he told SkyTG24 television. "The command systems did not function as they should have."

DEATH TOLL FEARS

There were fears the death toll could rise after considerable confusion on Saturday over the number of missing passengers.

Magistrates said Schettino, whose ship was carrying 4,229 passengers and crew, abandoned the vessel before all the passengers were taken off.

The vessel's operator, Costa Crociere, a unit of Carnival Corp & Plc, the world's largest cruise company, said the Costa Concordia had been sailing on its regular course when it struck a submerged rock.

In a television interview, Schettino said the rock was not marked on any maritime charts of the area.

Costa Crociere president Gianni Ororato said the captain "performed a maneuver intended to protect both guests and crew" but it was "complicated by a sudden tilting of the ship."

"We'll be able to say at the end of the investigation. It would be premature to speculate on this," said coastguard spokesman Filippo Marini.

After a night-time operation on Friday and Saturday involving helicopters, ships and lifeboats, many passengers had left the area with many taken to Rome airport for flights home.

The ship was involved in an accident on November 22, 2008 when it hit a port wall and was damaged while docking.

Local officials expressed concern the fuel on the ship, at full load as it had just begun the cruise, could spill into the pristine waters. However by early Sunday, there was no sign of any pollution damage.

DINNER TIME DISASTER

Passengers had just sat down to dinner, a few hours after leaving the port of Civitavecchia near Rome on a week-long cruise to Barcelona and Majorca, when a loud bang interrupted the piano player and the ship began to list.

"We heard a loud rumble, the glasses and plates fell from the tables, the ship tilted and the lights went off," said passenger Luciano Castro.

"What followed was scenes of panic, people screaming, running around the place. Close to us a five-month pregnant young woman was crying and panicking."

The ship was carrying mainly Italian passengers, but also many foreigners including British, Germans, French, Spanish and Americans.

Many were elderly and some were in wheelchairs.

It became more difficult to lower the lifeboats the more the ship listed.

"It was complete panic. People were behaving like animals. We had to wait too long in the lifeboats," said 47-year-old Patrizia Perilli.

Passengers said they had been given little or no information in the immediate aftermath of the ship running aground.

"After approximately 20 minutes a voice told us there was a problem with the electricity that they were trying to fix," said Castro.

"The ship continued to tilt further, after 15 minutes they said again it was a problem with the electricity, but no one believed it," he said.

"Of course panic makes things worse and the crew members struggled in calming down the most active and worried passengers."

The ship was built in 2004-2005 at a cost of 450 million euros at the Fincantieri Sestri shipyard in Italy.

(Additional reporting by Silvia Ognibene, Edward Taylor and Joern Poltz; Writing by Philip Pullella and James Mackenzie; Editing by Andrew Roche)