SEOUL, South Korea - South Korean prosecutors on Monday demanded the death penalty for the captain of a ferry that sank in April, killing more than 300 people, and life sentences to three key crew members, a court official said.

Ferry's captain under probe

Prosecutors also requested that a district court sentence 11 other crew members up to 30 years in prison on charges that they were negligent and failed to protect passengers when the ferry was sinking April 16, said an official at the Gwangju District Court in southern South Korea. He spoke on condition of anonymity, saying he wasn't authorized to speak to the media about the requested punishment.

The 15 crew on trial were among the first people rescued from the ship when it began badly listing en route from Incheon, west of Seoul, to the resort island of Jeju. Most of those who died in the disaster were students from a single high school who were on a field trip to the island.

Capt. Lee Joon-seok and the three key crew members _ a first mate, a second mate and the chief engineer _ were indicted in May on homicide charges. Eleven other crew members were indicted on less serious charges.

Court officials have said the court will issue verdicts on the 15 crew members in November.

The death penalty is the maximum legal sentence in South Korea, but the country has a de facto moratorium on capital punishment and has not executed anyone since December 1997. South Korean courts, however, still occasionally issue death sentences.

In video taken by the coast guard on the day of the sinking, Lee was seen escaping the ferry in his underwear to a rescue boat while many passengers were still on the sinking ship.

The sinking, one of South Korea's deadliest disasters in decades, caused nationwide grief and fury, with authorities blaming overloading of cargo, improper storage, untimely rescue efforts and other negligence for the incident.

More than six months after the sinking, the bodies of 294 people have been recovered, while 10 others have not been found. A total of 476 people were aboard the ship, with 172 of them rescued.

Lee has apologized for abandoning the passengers, but said he didn't know his action would lead to so many deaths.

Many student survivors have said they were repeatedly ordered over a loudspeaker to stay on the sinking ship and that they didn't remember any evacuation order being given before they helped each other flee the vessel.

Lee has said he issued an evacuation order for passengers. But he initially told reporters days after his arrest that he withheld the evacuation order because rescuers had yet to arrive and he feared for the passengers' safety in the cold, swift waters.

The defense in the trial has denied any collusion among the crew members, saying they were confused, injured and panicked.