South Korea's Coast Guard said on Tuesday that it carried out an emergency exercise near the Ieodo research station south of Jeju Island.
The exercise took place near the Ieodo Ocean Research Station, located 150 kilometers south of the resort island, and within the country's exclusive economic zone, authorities said.
Coast Guard cutters from Jeju and Seogwipo were used in the exercise that aimed to train crews to respond to emergency situations that can occur around the research station.
Two large cutters, four small speed boats and a helicopter were used in the training mission, which included Coast Guard special forces units arresting people who had broken into the Ieodo research station.
Completed in 2003, the station is a 1,320 square-meter steel-frame structure built on the reef and is designed to keep tabs on environmental change in the region. The facility can be operated without a crew although it can house eight researchers and repair personnel.