Chinese and Russian military aircraft intrude into Korea's Air Defense Identification Zone (KADIZ) (PG) Yonhap News

Nine Chinese and Russian military aircraft entered and exited South Korea's Air Defense Identification Zone (KADIZ) over the East Sea and South Sea on the morning of the 9th, the Joint Chiefs of Staff (JCS) announced.

The JCS stated, "Around 10 a.m. today, seven Russian military aircraft and two Chinese military aircraft sequentially entered and exited the KADIZ over the East Sea and South Sea, with no airspace violations occurring."

They added, "Our military identified the Chinese and Russian military aircraft from before their entry into the KADIZ and deployed Air Force fighter jets to conduct tactical measures in preparation for contingencies."

The Chinese and Russian military aircraft that entered the KADIZ were bombers and fighter jets. It was reported that four Russian military aircraft and two Chinese military aircraft were part of the forces participating in joint Sino-Russian exercises.

A JCS official explained, "Russian military aircraft entered the KADIZ in the direction of Ulleungdo and Dokdo, while Chinese military aircraft entered the KADIZ in the direction of Ieodo. The two countries' military aircraft rendezvoused in the airspace near Tsushima Island."

The Chinese and Russian military aircraft are reported to have been within the KADIZ for approximately one hour.

The official mentioned, "Chinese and Russian military aircraft conduct joint exercises in the airspace near the Korean Peninsula about once or twice a year." He added that Chinese and Russian military aircraft had previously entered the KADIZ during joint exercises on November 29th of last year.

An Air Defense Identification Zone (ADIZ) is an arbitrary line established to identify and respond to military aircraft approaching a country's airspace at an early stage; it is a different concept from sovereign airspace, which is a matter of individual state sovereignty.

It is international practice for military aircraft entering another country's ADIZ to submit their flight plans in advance and notify their location upon entry.

However, Russia does not recognize South Korea's control over the KADIZ, arguing that it lacks a legal basis under international law. The airspace over Ieodo, where Chinese military aircraft entered, is an area where the ADIZs set by South Korea and China overlap.

A military official stated, "We have a direct line with the Russian Navy, and upon inquiry about their entry into the KADIZ, we received a response that it was routine training and that they would not violate sovereign airspace."

The official added, "We do not have a direct line with China, so we could not inquire. The KADIZ over Ieodo, where Chinese military aircraft entered, is an overlapping area of the South Korean and Chinese ADIZs, and Chinese aircraft enter this area approximately 90 to 100 times per year."