The South Korean Ministry of Defense said that “dozens of Chinese and Russian warplanes have entered the Korean Air Defense Identification Zone over the past year.”

“The number of Chinese warplanes infiltrating the Korean air defense identification zone in 2021 exceeded 70 times, which is the same as the previous year,” the document submitted to parliament said.

The Ministry of Defense indicated that “the number of visits by Russian aircraft to the specified area over the past year has exceeded 10 times,” and “Japanese combat aircraft entered the overlapping air defense areas of the two countries with a frequency of 500 times a year, but after prior notification.”

The air defense zone was first established in 1951 by the US Air Force during the Korean War of 1950-53 to prevent air clashes between countries surrounding the Korean Peninsula. This area is not considered regional airspace, but is intended for foreign aircraft to identify themselves to avoid accidental collisions.