Japan investigates captain after warship enters China’s territorial waters despite warnings

A Japanese Maritime Self-Defence Force destroyer temporarily sailed into Chinese territorial waters off the country’s eastern province of Zhejiang last week, despite repeated warnings by Chinese vessels, diplomatic sources said on Wednesday.

The Suzutsuki, tasked with monitoring Chinese military drills on the high seas, navigated into Chinese waters on July 4, in a rare move by a Self-Defence Forces vessel.

Beijing has conveyed its serious concern to Tokyo over the incident, leading the Japanese defence ministry to launch an investigation into the ship’s captain, the sources said. The ministry declined to comment on matters concerning SDF operations.

A day before the MSDF destroyer entered Chinese waters, Zhejiang authorities said a no-sail zone would be set up in a nearby area for the Chinese military to conduct a live-fire drill, opening up the risk of a contingency occurring because of the Suzutsuki’s presence.

The Chinese government suspects the incident was an “intentional provocation” by the destroyer, and has been collecting and analysing relevant information, according to Chinese sources.

The Suzutsuki, which was on a mission to monitor the live-fire drill, was urged by the Chinese vessels to leave the area when it approached within 12 nautical miles (22km) off the coast of Zhejiang, but it sped up and navigated into the Chinese waters for some 20 minutes before leaving the territorial waters, the diplomatic sources said.

The MSDF ship has in the past monitored the activities of the Chinese aircraft carrier Liaoning, deployed in the East China Sea, but Japanese destroyers tasked with surveilling Chinese vessels usually stay away from territorial waters off Zhejiang, they added.

In unofficial talks between the two sides,