Dozens of teenagers who survived South Korea's ferry disaster returned to school Wednesday for the first time since the deadly accident in April.

As the 73 second-year students walked from a bus to Danwon High School in the city of Ansan, some "bowed their heads as they cried and ... some stopped to hug the parents of their friends, who caressed their hair and face," The Associated Press reports.

A banner at the entrance to school declared, "We pray the dead will rest in peace."

Of the 476 people who were on board the ferry when it sank, 323 of them were second-year Danwon students on a class trip. Only 75 students were rescued — 245 died and five are still missing, according to the AP.

Officials say two of the survivors had already returned to school; the rest had been attending classes and therapy sessions at a facility in Ansan.

Shin Young-jin, one of the survivors, gave an emotional address in which he called for a thorough investigation of the ferry accident, according to the AP. He also said that while many people have offered condolences, others have accused the students of betraying their dead classmates by surviving.

"Whenever we heard such things, our hearts tore apart and ached and we shed tears because we felt guilty and sorry for our friends," Shin said. The AP continues:

" 'Just as we cannot forget them, we ask that the citizens of this country also never forget them,' Shin said of the dead, stopping at one point as tears choked his words. 'For the adults who lead us, we ask that you exhaustively search for those responsible for this crime.' "

As we previously reported: "The ferry, called the Sewol, was nearing the end of what should have been a 14-hour or so trip south from the city of Incheon to the resort island of Jeju on April 16 when it ran into trouble, capsized and sank."

"The ferry's captain and many of its crew have been arrested. Among the issues authorities are investigating is why the order to evacuate wasn't given for at least 30 minutes. The captain and most of the 29-member crew survived. Seven crew members are known to have died or are missing, though, and a few of them have been hailed as heroes who tried to get passengers off the ferry before it went down."

The BBC says the surviving students will be involved in the criminal case against the ferry's captain and some of its crew:

"Captain Lee Joon-seok and 14 crew members have been accused of prioritizing their own safety over that of passengers, and also of causing more deaths by instructing people to remain in their cabins instead of evacuating the ship.

"The students who survived are due to testify next month for that trial, and will testify by closed-circuit television from a courtroom in Ansan."

Click here to see more of our coverage of the Sewol disaster.

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