TEHRAN, Young Journalists Club (YJC) -Kukmin Ilbo reported Wednesday two Russian Tupolev Tu-142 aircraft entered the KADIZ starting about 8:02 a.m. on Friday, after exiting the JADIZ, or Japan's Air Defense Identification Zone.
South Korea responded with F-15K fighter jets, but soon after Russia told the South the aircraft were en route to a training exercise, according to the report.
The Tu-142 is a Russian maritime reconnaissance and anti-submarine warfare aircraft. On Friday, the planes had entered Korea's air defense zone a total of four times, while flying over the Sea of Japan, or the East Sea.
The Japan Joint Staff were the first to make public the Russian maneuvers in the KADIZ, according to the Kukmin. South Korea's military said they decided not to publicize the incident because "no special movements" were detected, the report says.
Last July, South Korea also scrambled fighter jets after two Russian military planes entered the KADIZ multiple times. South Korea's joint chiefs at the time did issue a statement.
On Friday, the Russian aircraft were going to an exercise being held in Qingdao, China, that took place from April 29 through Saturday.
Russia and China are cooperating more closely on international issues, and Beijing's top diplomat Wang Yi is to travel to Moscow on Sunday, South Korean news agency Yonhap reported.
China's foreign ministry said Wang is traveling upon the invitation of Russian Foreign Minister Sergey Lavrov, while the two sides celebrate 70 years of diplomatic ties.
Russia's Tass news agency reported Lavrov is to meet with U.S. Secretary of State Mike Pompeo on Tuesday.