South Korean military attaché was handed a protest note on Tuesday after “the illegal and dangerous actions by the pilots of S. Korean fighter jets,” Russian long-range aviation commander, Lt. Gen. Sergey Kolybash, said on Tuesday.

The Russian planes strictly followed the pre-set flight routine, he said. “The Russian aircraft have not violated the airspace of South Korea and Japan… Therefore, the actions by the South Korean pilots should be regarded as air hooliganism,” Sputnik quoted the general as saying.

The military in Seoul said earlier in the day that Russian  aircraft had illegally crossed into South Korean airspace twice over the Sea of Japan, and that F-16 fighters fired warning shots in response.

The Russian Defense Ministry said that the South Korean fighters had performed non-professional maneuvers. The ministry has accused South Korea of repeatedly trying to impede Russia’s flights over the Sea of Japan’s/East Sea’s neutral waters, referring to an “air defense identification zone” unilaterally imposed by Seoul that is not envisaged in international regulations or recognized by Russia.