Experts say South Koreans trapped on ferry could have survived 72 hours if they found air pockets

SEOUL, South Korea — Desperate search and rescue efforts for hundreds still unaccounted for in a deadly ferry accident in waters off South Korea's southwestern coast continued for a fourth day on Saturday, with the whole country clinging to dim hope of finding survivors.

Hundreds of Navy and Coast Guard officers, along with civilian divers, have been battling strong underwater currents and low visibility to reach 273 people believed to be trapped inside the ferry Sewol that sank three days ago.

More than 72 hours have passed since the 6,825-ton ship sank off the southwestern island of Jindo on a foggy Wednesday morning. A total of 476 passengers, including 325 high schoolers on a field trip, were aboard the ship en route to the southern resort island of Jeju from the western port of Incheon.

As of 11 a.m., 29 passengers had been confirmed dead. While 174 have been rescued, no one has been found alive since around Wednesday noon when the ship went under.

"We've yet to get any response from survivors underwater. Divers have continued all-out operations to enter cabins, while pumping air to help them breathe," Coast Guard officer Choi Sang-hwan said.

Experts say people could possibly survive for 72 hours if there are air pockets in the compartments.

"Instead of dispatching two divers at a time, we are to send up to 10 workers at the same time to speed up the job. We are working to install more guide lines" he said, referring to lines that help workers move inside vessels.

During overnight operations, divers found three dead bodies wearing life jackets inside the cabin on the fourth floor of the five-story ferry, officers said, adding they are trying to break the window to recover them.

"As weather conditions are forecast to worsen in the afternoon, we will do everything to make progress in the morning," Choi added.

With investigations into what caused the tragedy under way, the joint probe team of prosecutors and police detained the 68-year-old captain, surnamed Lee, and two other crew members earlier in the day for their negligence of duty and violation of maritime law.

According to the interim probe result announced a day earlier, the captain was at the steering room when the boat was experiencing trouble. He had given the wheel to an inexperienced third mate in her 20s.

Denying some accounts that he was drinking at the time the ship experienced problems, Lee said he was not in the steering room and had "gone to his bedroom after giving instructions on which route to follow."

Lee was also accused of abandoning the boat while hundreds of passengers were desperately struggling to find their way out. A public uproar has erupted as crew members repeatedly told the passengers to remain seated though the ship was foundering, stripping them of their chance to escape.

While apologizing to victims and their families, the captain denied the allegations that he failed to instruct passengers to leave the vessel.

"I gave such an order [to passengers to evacuate]," captain Lee told reporters upon being arrested.

Asked about why he told people to remain seated, he said, "It was before any rescue vessels had arrived, and the water was cold."

The 55-year-old steersman who guided the boat with the female mate said he navigated the ship just as he normally does, but the steering gear "turned exceptionally faster than normal."

Experts and investigators have said a sudden shift of the vessel caused 180 vehicles and 1,157 tons of freight on board to slid to one side, disrupting the balance of the ship.

The investigation team is also planning to investigate some 10 crew members, as well as officials of the Sewol's operator, Cheonghaejin Marine Co., according to officers.

The Coast Guard, meanwhile, said they are considering surrounding the shipwrecked spot in a net to prevent bodies of possible victims from being swept away by the strong underwater currents. So far, they have not consider the option, as it would hamper divers' search operations.

The point of the accident, named the Maenggol Channel, is notorious for strong underwater currents in the country.