SEOUL — All 15 people involved in navigating the South Korean ferry that sank and left more than 300 people dead or missing are now in custody after authorities on Saturday detained four more crew members, a prosecutor said.
Yang Jung-jin of the joint investigation team said two helmsmen and two members of the steering crew were taken in on preliminary arrest warrants issued late Friday. Eleven other crew members, including the captain, had been formally arrested earlier.
All are accused of negligence and of failing to help passengers in need as the ferry Sewol sank April 16. The captain initially told passengers to stay in their rooms and took half an hour to issue an evacuation order, by which time the ship was tilting too severely for many people to get out.
On Sunday, South Korea’s prime minister offered to resign over the government’s handling of the sinking, blaming ‘‘deep-rooted evils’’ and societal irregularities for the tragedy.
South Korean executive power is largely concentrated in the president, Park Geun-hye, so the resignation offer by Prime Minister Chung Hong-won appears to be largely symbolic. There was no immediate word from Park about whether she would accept Chung’s resignation.
Ten days after the sinking, 187 bodies have been recovered and 115 people are believed to be missing, though the government emergency task force has said the ship’s passengers list could be inaccurate. Only 174 people survived, including 22 of the 29 crew members.
A court hearing was held Saturday to determine whether formal arrest warrants will be issued against the four newly detained crew members. South Korean television aired video of the police escorting the four men to court. All four wore baseball caps that hid their faces, and at least one was limping.
Captain Lee Joon-seok told reporters after his arrest that he withheld the evacuation order because rescuers had yet to arrive and he feared for passengers’ safety in the cold water. Crew members have also defended their actions.
Helmsman Oh Yong-seok, one of those arrested Saturday, has said he and several crew members did their best to save people. He said that he and four crew members worked from nearby boats to smash windows on the sinking ferry, dragging six passengers stuck in cabins to safety.
Officials in charge of the search effort said divers have reached two large rooms where many of the lost may lie dead, but the search had to be suspended because of bad weather. Currents were already strong Saturday morning, as they were in the first several days of the search, when divers struggled in vain even to get inside the submerged vessel.
The two rooms where searchers hope to find more of the missing soon are sleeping units designed for many people. Fifty students from Danwon High School in Ansan were booked into one of them. Students from the city near Seoul make up more than 80 percent of the dead and missing; they had been on their way to the southern tourist island of Jeju.
Large objects that toppled when the ferry tipped over and sank are believed to be keeping divers from reaching bodies in at least one of the rooms.
Also Saturday, the Ministry of Oceans and Fisheries said it would soon change ferry systems so that passenger, vehicle, and cargo information is processed electronically.
There is not only uncertainty about how many people were on the Sewol, but a huge discrepancy regarding the amount of cargo it was carrying.
The ministry said that starting June 1, passengers’ names, genders, birthdates, and contact information will be electronically entered when they get their boarding passes. Vehicles and cargo will be electronically processed beginning July 1, the ministry said.