during a joint air patrol Tuesday.

The alleged violation happened near a disputed group of islands claimed by both South Korea, which calls it Dokdo, and Japan, which calls it Takeshima.

South Korea's Defense Ministry says it scrambled multiple fighter jets after a Russian warplane ventured into its airspace over the East Sea.

The ministry says after the South Korean jets fired warning shots, the Russian plane left South Korean territory. However, it returned a short time later, prompting the South Korean jets to fire more warning shots.

Russia's Defense Ministry denied Seoul's depiction of the incident, and accused the South Korean fighter jets of "unprofessional maneuvers." A spokesman for China's Defense Ministry told reporters in Beijing that the patrol did not "target any third party" and flew along established air routes.

South Korea's Defense Ministry summoned officials from the Chinese and Russian embassies to lodge an official protest. Seoul says this is the first time that a Russian plane has violated its territorial skies.

The flight by two Russian and two Chinese bombers, plus early warning planes from both nations, marks a notable ramping-up of military cooperation between Beijing and Moscow.

Japan also lodged its own formal protest with Seoul and Moscow over the incident. Chief Cabinet Secretary Yoshihide Suga told reporters in Tokyo that South Korea's actions were "totally unacceptable and extremely regrettable" in light of Japan's claim over the islands.