●On March 23, 1999, a Maritime Self-Defense Force's P-3C patrol aircraft conducting precautionary surveillance discovered a boat that could be judged as a spy vessel. The destroyers headed for training confirmed the boat's name and immediately reported it to the Japanese Coast Guard.
●A Coast Guard patrol vessel took measures against the suspicious boat, including firing warning shots, but pursuit became difficult.
●Early in the morning of the 24th, orders were issued to the Maritime Self-Defense Force to conduct maritime security operations. This was the first time
such an order was given to the Maritime Self-Defense Force after their formation.
●The destroyers ordered the boat to stop, and also fired warning shots, but the boat continued to flee.
●Even after the boat left Japan's Air Defense Identification Zone (ADIZ), the P-3C patrol aircraft continued tracking the bout with its radar from within the ADIZ. Nothing untoward happened in the areas around Japan, however, so the maritime security operations were discontinued.
●An order for maritime security operations was issued as a result of this incident. It is thought to have increased the deterrence of similar incidents in the future. Also, considering the lessons learned from this incident and the reappraisal of our actions after the incident, the "Manuals on Joint Strategies concerning Suspicious Boats" was complied, prescribing the specific roles of the Maritime Self-Defense Force and the Coast Guard, and the particulars of the joint response. The ships and aircraft that were engaged in this activity:" HARUNA"," MYOKO"," ABUKUMA"," P-3C"