The plan is said to have flown through the South Korean air defense's so-called identification zone (Adiz), which is a unilaterally declared surveillance area that extends beyond a country's territory and airspace.
This happened in stages during the morning and afternoon, according to a spokesperson for the South Korean military's general staff to Yonhap. South Korean planes took off to mark a "tactical measure", it was further announced.
In addition to this, Taiwan is warning of new flybys by Chinese planes. 41 planes have been observed in connection with the Taiwanese President Lai Ching-Te's trip to countries around the Pacific, starting in Hawaii, USA. Chinese military planes, ships, or drones have passed Taiwan almost daily in recent times.
Russia's Defense Minister Andrej Belousov arrived early on Friday in North Korea for an official visit, according to state-run Russian media. Russia has established new military agreements with the isolated North Korea during its ongoing invasion war in Ukraine, including a pact where the countries will defend each other in the event of an attack.