The destroyer Suzutsuki reportedly sailed for about 20 minutes within 12 nautical miles (22 kilometers) of China's Zhejiang Province coast on July 4. When questioned, the commander in charge claimed he was unaware the vessel had entered a restricted area, according to the sources.
This marks the first time an MSDF ship has entered Chinese waters without prior notification since the force's establishment in 1954. The incident has raised concerns about the competency of MSDF personnel and prompted Tokyo to consider disciplinary actions against other crew members.
Japan has unofficially informed China about its findings and the captain's removal. While Tokyo maintains the entry was lawful under international maritime law, Beijing has criticized it as "illegal and improper," demanding a thorough investigation.
Yoji Koda, former commander in chief of the Self-Defense Fleet, attributed the incident to inadequate training. He said that MSDF officers won't be able to fully develop the basic skills necessary to operate the force's vessels if they spend a significant amount of time on surveillance activities, calling on the Japanese government to increase personnel and equipment.