A South Korean destroyer that allegedly directed fire-control radar at a Maritime Self-Defense Force patrol plane earlier in the week locked it for a few minutes, Japanese government sources said Saturday.
Given such a duration of radar lock, Japanese government officials believe the South Korean ship aimed its radar at the MSDF P-1 aircraft on purpose, despite Seoul's explanation it was not used to track the plane.
The Defense Ministry on Saturday called the incident, which occurred Thursday, "extremely regrettable" and urged South Korea to prevent a recurrence of such a "dangerous act" that could have led to a contingency.
The ministry said, following its "careful and detailed" analysis, it judged that fire-control radar -- designed to accurately measure the direction and distance of a targeted object before launching an attack -- was used by the South Korean Navy.
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South Korean warship directs fire-control radar at Japan plane
The South Korean destroyer equipped with anti-aircraft and anti-ship missiles was running within Japan's exclusive economic zone outside its territorial waters off the coast of Ishikawa Prefecture, central Japan, at the time of the incident, according to the ministry.
South Korean media reports say the South Korean Navy vessel was in operation to help a North Korean ship drifting near a sea border.
One Japanese government source rejected South Korea's explanation, saying, "Had it been done by chance, the directing of radar on the MSDF aircraft should have ended instantly. It was done intentionally."
The Japanese government will likely demand detailed explanations from South Korea before deciding whether to take further action.
The incident came amid chilling diplomatic ties between Tokyo and Seoul due to recent court rulings in South Korea that ordered major Japanese companies to pay compensation for wartime forced labor. Japan has maintained that the issue of compensation has been settled "completely and finally" when the basic bilateral relations treaty was signed in 1965.
Kenji Kanasugi, director general of the Asian and Oceanian Affairs Bureau at the Foreign Ministry, is expected to meet with South Korean Foreign Ministry officials and raise the radar issue when he visits Seoul from Sunday to Tuesday.
