On 22 December 2001, the Battle of Amami-Ōshima was a six hour long confrontation with an undercover North Korean spy and infiltration ship. The spy ship was heavily armed and 400 km north west of the Japanese island Amami Ōshima. The spy ship didn't heed warnings of the Japanese Coast Guard and tried to escape. 12 patrol boats and 13 planes of the JCG and 2 MSDF destroyers chased the ship. Eventually the spy vessel opened fire and, after receiving fire from JCG cutters, sunk with self-destructive explosion. All 15 crew members died. This was the first time since World War 2 that Japan attacked and sank a foreign ship in Japan's sea territory.