South Korea has lodged a formal protest with China and Russia after their warplanes entered its air defense zone, sparking a swift response from Seoul’s military. The complaint was filed with the defense attaches of both countries in the South Korean capital, a day after the incident occurred.

According to Seoul, the planes were spotted before they entered the Korea Air Defence Identification Zone (KADIZ), a broader area where countries monitor aircraft for security reasons. In response, South Korea deployed fighter jets to take tactical measures in preparation for any contingencies. The KADIZ is not the same as airspace, but rather a designated area where countries can track and respond to aircraft.

Beijing confirmed that it had conducted joint drills with Russia’s military as part of “annual cooperation plans,” while Moscow described the exercise as routine, lasting eight hours. The Russian and Chinese aircraft were reportedly followed by foreign fighter jets during the drill.

This incident is not an isolated event, as China and Russia have regularly flown military aircraft into South Korea’s air defense zone without prior notice since 2019, citing joint exercises. Similar incidents occurred in November last year, as well as in June and December 2023, and in May and November 2022. Each time, Seoul has scrambled jets in response.

The South Korean military has vowed to continue responding actively to the activities of neighboring countries’ aircraft within the KADIZ, in compliance with international law. The director general of the International Policy Bureau at Seoul’s defense ministry, Lee Kwang-suk, emphasized the importance of adhering to international law in such situations.

The incident highlights the ongoing tensions in the region, with South Korea seeking to protect its airspace while China and Russia engage in joint military exercises. As the situation continues to unfold, Seoul’s military remains on high alert, ready to respond to any further incursions into its air defense zone.