The defendants were found guilty of battering 34-year-old Le Quang Huy to death, before throwing his body to the sea on August 2, according to the report on the trial at the criminal court of Daegu City, about 300 kilometers from Seoul.
The killing was an act of revenge, as the Indonesian nationals had conflicts with the victim, who was tasked with supervising and coordinating work among the crew, during their four years working together, the court heard on February 17.
|A file photo of three of seven Indonesian crew members of a RoK fishing ship detained at a police station for murdering their Vietnamese colleague on August 2, 2015.
While the murder took place when the ship was offshore, Korean maritime police discovered blood on the back of the ship and on one of the defendants' shirt.
Police then stepped in with a DNA test and interrogated the suspects, the news agency reported.
Registered in Busan City, the ship is operated by a crew of nine Indonesian, eight Philippine, seven Korean and 11 Vietnamese members.
The Vietnamese embassy to South Korea was notified of the case two days after it happened.