The Defense Ministry says a Russian aircraft twice flew into Japan's airspace over the eastern tip of the Shiretoko Peninsula in Hokkaido on Sunday morning. The Air Self-Defense Force scrambled fighter jets, and the plane left the area after the fighters warned it to leave by radio.
On Monday, Chief Cabinet Secretary Kato Katsunobu told reporters that the government lodged a protest through senior diplomats in Tokyo and Moscow on the previous day, urging the Russian side to prevent a recurrence.
Kato said that the government is analyzing why the Russian plane entered the airspace. He added that he wants to refrain from commenting on the reason for the violation of airspace.
The Defense Ministry said on Sunday that the Russian plane was an Antonov An-26 transport aircraft.
Earlier, it was reported that Belarus wanted to place S-400 anti-aircraft missile systems on the border with Ukraine, which they plan to buy in Russia. The statement came from President of Belarus Alexander Lukashenko.