Updated

Divers on Monday renewed their search for more than 100 bodies still trapped in a sunken ferry after weekend efforts were hindered by bad weather, strong currents and floating debris clogging the ship's rooms. Officials said they have narrowed down the likely locations in the ship of most of the remaining missing passengers.

Divers found only one body Sunday after a week that saw an increasing number of corpses pulled from the ship as divers made their way through its labyrinth of cabins, lounges and halls. The number of dead from the April 16 sinking is 188, with 114 people believed missing, though a 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.

Senior coast guard officer Kim Su-hyeon said that most of the remaining missing passengers are believed to be in 64 of the ship's 111 rooms. Divers have entered 36 of those 64 rooms, coast guard officers said, but may need to go back into some because floating debris made it difficult for divers to be sure that there are no more dead bodies.

Ko Myung-seok, an official with the emergency task force, said Monday that 92 divers would search the ferry. He also said that the government was making plans to salvage the ferry once search efforts end but that details wouldn't be available until officials talk with families of the victims.

On Sunday, South Korea's prime minister resigned over the government's handling of the sinking, blaming "deep-rooted evils" in society for the tragedy.

South Korean executive power is largely concentrated in the president, so Chung Hong-won's resignation appears to be symbolic. Presidential spokesman Min Kyung-wook said President Park Geun-hye would accept the resignation, but did not say when Chung would leave office.

Chung's resignation comes amid rising indignation over claims by the victims' relatives that the government did not do enough to rescue or protect their loved ones. Most of the dead and missing were high school students on a school trip.

Officials have taken into custody all 15 people involved in navigating the ferry Sewol, which sank April 16. The seven surviving crew members who have not been arrested or detained held non-marine jobs such as chef or steward, according to senior prosecutor Yang Jung-jin.

The arrested crew members are accused of negligence and of failing to help passengers in need. Capt. Lee Joon-seok 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.

Lee 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, swift water.

In video released Monday by the Coast Guard, the captain, Lee Joon-seok, wearing only a sweater and underpants is shown leaping from the sinking ferry, which is tilted about 45 degrees, onto a rescue boat. According to Kim Kyung-il, a coast guard official, the ship's crew members did not tell rescuers that they were crew members.

The Ministry of Oceans and Fisheries said it would soon change its ferry monitoring 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 when it sank.

The ferry was carrying an estimated 3,608 tons of cargo, according to an executive of the company that loaded it. That far exceeds what the captain claimed in paperwork -- 150 cars and 657 tons of other cargo, according to the coast guard -- and is more than three times what an inspector who examined the vessel during a redesign last year said it could safely carry.

Yang, the prosecutor, said that the cause of the sinking could be due to excessive veering, improper stowage of cargo, modifications made to the ship and tidal influence. He said investigators would determine the cause by consulting with experts and using simulations.

Yang said that a crew member called the ship's owner, Chonghaejin Marine Co. Ltd., as the ferry was listing, but declined to disclose whether the caller was the captain. Local media reported that the captain called for company approval of an evacuation. Prosecutors said they are analyzing the content of communications between the ship and the company.

Students from Danwon High School in Ansan, a 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.