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. The seven surviving crew members who have not been arrested or detained held non-marine jobs such as chef or steward, Yang said in a telephone interview from Mokpo, the southern city near the wreck site where prosecutors are based. A court hearing was held on 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. Capt. 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 on 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 on Saturday that 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. “This morning (the divers) did a primary dive, but because of the strong current they were losing their masks, so we have stopped the dive for now,” Kim Jin-hwang, a South Korean navy official in charge of commanding the dive search, said in a briefing at Jindo. He said the search would resume once conditions improve, but it was unclear when that would happen. The two rooms where searchers hope to find more of the missing soon are sleeping units designed for many people — one in the stern and one in the bow. 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. “Many structures ... all fell down as the ship listed, and now are all buried on the left side. Because of the weighty objects it was impossible to entirely search the room,” Kim said. — AP