April 19, 2014 9:17 AM EDT

Updated 11:24 pm

The death toll on the South Korean ferry that capsized Wednesday has risen to 49.

Over a dozen bodies were discovered by divers inside the ferry, according to officials Sunday, the Associated Press reports. It came after three days of unsuccessful attempts because of strong currents and bad weather.

More than 250 passengers are missing from the ferry, a large number of them high school students who were on a school trip to the holiday island of Jeju.

The ferry’s captain, Lee Joon-seok, was arrested Saturday on charges of negligence of duty and violation of maritime law. Prosecutors bringing charges said Lee escaped the ship before the passengers, CBS reports. Two crew members were also arrested, including a rookie third mate who prosecutors said was unfamiliar with the strong current off the South Korean coast.

Lee had four decades of experience at sea, but he was not the ferry’s main captain and told reporters he was not on the bridge when the ferry began tilting. He also said that he told children on board to stay on the sinking ship for fear they would be swept out to sea in the strong, cold current, Reuters reports.

Lee waited 30 minutes before finally issuing an evacuation order, by which time the ship had already sloped too far on its side for people to escape the tight hallways and stairs inside the sinking vessel. Several survivors said they never heard the order to evacuate.

Investigators said the accident occurred at a point along the route where the ship had to make a turn through islands with strong currents. Prosecutors are examining whether the inexperienced third mate ordered a turn too sharp, causing the vessel to list.

With the chances of survival among any of the missing passengers increasingly slim, the accident is shaping up to be the deadliest Korean maritime accident in 21 years. The 323 students on board were from Danwon High School in Ansan and were aged 16 and 17.

The school’s vice president, who was rescued as the children stayed aboard, hanged himself Friday outside a gym in Jindo where relatives of survivors were put up.



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