Three Chinese fishermen whose fishing boat was seized by the Korea Coast Guard for illegally fishing inside South Korean waters died when their boat caught fire.
The dead Chinese were part of a 17 man crew whose boat was stopped and boarded by the coast guard. Instead of surrendering, the victims barricaded themselves in the wheelhouse.
The coast guardsmen then threw a stun grenade or a "flashbang" into the wheelhouse. The grenade exploded and ignited a fire that eventually engulfed the wheelhouse and the boat.
The South Koreans believed the dead men died of smoke inhalation and an autopsy has been ordered. The 14 survivors were taken to South Korea for questioning.
The Chinese boat was caught fishing off the southwest of the Korean peninsula, some 70 km southwest of Hongdo Island.
China's Ministry of Foreign Affairs lodged a protest with Seoul about the incident. Spokesman Geng Shuang urged South Korea to hold a "comprehensive and objective" investigation into the incident along with China.
Korea Coast Guard vessels regularly chase Chinese boats for fishing illegally and there have been violent confrontations in the past. Fishing in South Korean waters by Chinese vessels is permitted but with the proper authorization from South Korean authorities.
Last June, South Korea sent its ships from its navy to chase off Chinese fishing boats illegally harvesting prized blue crabs near the disputed sea boundary between the Koreas.
Four naval and marine boats entered neutral waters around South Korea's Ganghwa island to chase away about 10 Chinese boats, which escaped into North Korea-controlled waters. The operation was approved by the United Nations Command that governs the zone where fishing is prohibited.