Lee Joon-Seok (C), captain of the South Korean ferry "Sewol" which sank at sea off Jindo, is investigated at Mokpo police station in Mokpo April 17, 2014. Rescuers were hammering on the upturned hull of the capsized South Korea ferry on Thursday hoping for a response from hundreds of people, mostly teenage schoolchildren, believed trapped after the vessel started sinking more than 24 hours previously. [Photo/Agencies]

MOKPO, South Korea - The captain of a sunken South Korean ferry was arrested Saturday on suspicion of negligence and abandoning people in need, as investigators looked into whether his evacuation order came too late to save lives. Two crew members were also arrested, a prosecutor said.

Passengers wait for words

'I am sorry,' captain says

The disaster three days ago left more than 270 people missing and at least 29 people dead.

As the last bit of the sunken ferry's hull slipped Friday beneath the murky water off southern South Korea, there was a new victim: a vice principal of the high school whose students were among the passengers was found hanged, an apparent suicide.

The Sewol had left the northwestern port of Incheon on Tuesday on an overnight journey to the holiday island of Jeju in the south with 476 people aboard, including 323 students from Danwon High School in Ansan. It capsized within hours of the crew making a distress call to the shore a little before 9 a.m. Wednesday.

Only its dark blue keel jutted out over the surface. But by Friday night, even that had disappeared, and rescuers set two giant beige buoys to mark the area. Navy divers attached underwater air bags to the 6,852-ton ferry to prevent it from sinking deeper, the Defense Ministry said.

The coast guard said divers began pumping air into the ship to try to sustain any survivors.

Strong currents and rain made it difficult to get inside the ferry. Divers worked in shifts to try to get into the vessel, where most of the passengers were believed to have been trapped when it sank, coast guard spokesman Kim Jae-in said.

Investigators said the accident came at a point where the ship had to make a turn, and prosecutor Park Jae-eok said investigators were looking at whether the third mate ordered a turn that was so sharp that it caused the vessel to list.

The sharp turn came between 8:48 am and 8:49 am, but it's not known whether it was done voluntarily or because of some external factor, said Nam Jae-heon, a spokesman for the Maritime Ministry.

Another angle being probed is the role of the captain, 68-year-old Lee Joon-seok.

Senior prosecutor Yang Jung-jin said Lee was detained early Saturday, along with the two crew members. Lee faces five charges including negligence of duty and violation of maritime law, according to the Yonhap news agency.

Yang said earlier that Lee was not on the bridge when the ferry was passing through an area with many islands clustered closely together, something he said is required by law so the captain can help a mate make a turn. The captain also abandoned people in need of help and rescue, he said.