A crew member of a South Korean Navy vessel has gone missing while on a patrol mission near the Northern Limit Line (NLL) in the East Sea, prompting a search operation by military authorities.

The Navy stated, "A crew member serving on a Navy vessel on a patrol mission went missing this morning (July 12) in waters approximately 50 kilometers east of Geojin-eup, Goseong-gun, in the East Sea."

The missing sailor is reported to be a private first class serving on a frigate.

The sailor was last seen in an interior passageway of the ship by a fellow crew member who was on duty between midnight and 2:00 a.m. today.

It was later discovered that the sailor was missing when he failed to report for his duty shift at 8:00 a.m.

The Navy, in coordination with the Korea Coast Guard, has deployed over 10 vessels and several aircraft to search for the missing sailor.

The incident has also been notified to the North Korean side through the international merchant ship communication network, which is also accessible to North Korea.

Minister of National Defense Ahn Gyu-baek received a report on the incident and ordered that every effort be made to rescue the missing sailor as quickly and safely as possible.

The Ministry of National Defense added that the Minister also instructed the military to maintain an active cooperative system with relevant agencies, including the Korea Coast Guard.

Reported by Jeong Gyeong-yun | Video by Na Hong-hee | Graphics by Lee Jeong-ju | Produced by SBS Digital News