June 19 (UPI) -- A South Korean sailor was killed when ammunition exploded on a naval frigate off the southern coast.
The petty officer, identified only by his surname Lee, was pronounced dead at a hospital in the nearby city of Busan, after being transferred to medical care by naval helicopter, Yonhap reported.
Lee, 20, was from the South Korean city of Changwon, in South Gyeongsang Province. He entered the military in March 2017, after graduating from high school.
The sailor received three months of training and began to work on the 1,500-ton Masan naval frigate around July or August of last year, according to the report.
The officer was a trainee under the South Korean Navy's education command. The navy plans to provide financial support for the funeral.
"Details of the accident will be disclosed publicly when the family of the deceased is ready," a naval official said. "When the cause is finally identified, [information] will be released to the press."
The accident took place at 12:30 p.m. on Tuesday about 25 nautical miles south of an island near the city of Tongyeong.
Lee suffered critical injuries to his head and back.
The navy has said the explosion occurred while the officer was removing ammunition from a 30mm gun to prepare for live-fire drills.
News 1 reported the precise cause of the explosion would be determined after the Masan FFK-955 docks at a nearby port.
The Masan left Jinhae port in South Gyeongsang Province on Monday morning. On board were more than 120 sailors.
The frigate was launched on Oct. 26, 1984, and put into commission on July 20, 1985. It is one of the oldest frigates in operation.