Aug. 26 (UPI) — Japan scrambled fighter jets after a Chinese military plane, for the first time, violated the island nation’s airspace, the Japanese government confirmed Monday.

According to Japan’s Defense Ministry, a Y-9 intelligence-gathering plane at about 11:29 a.m. local time flew over the East China Sea near the Danjo Islands off the southwestern prefecture Nagasaki for roughly two minutes.

The incursion prompted the Air Self-Defense Force to scramble its fighter jets, defense ministry officials said.

The Y-9 reportedly circled above the water southeast of the islands multiple times before it entered Japanese airspace and before flying back toward China at about 1:15 p.m. local time.

Japan’s Vice Foreign Minister Masataka Okano summoned China’s Charge d’Affaires Shi Yong on Monday to issue an “extremely serious protest” and “strong request” over the airspace intrusion, Kyodo News and Japan Times reported.

Japan said it wants to ensure a similar flight won’t occur, the Foreign Ministry said. At the meeting, the Chinese diplomat said officials “would report the matter to their home country.”

The two nations have been at an impasse for some time now over the area around the uninhabited islands in the East China Sea. Chinese coast guard vessels also have reportedly entered Japanese territorial waters multiple times.

Last year, Japan’s Self-Defense Force scrambled fighter jets to intercept foreign planes 669 times, according to Japan’s Ministry of Defense. And of those 669 cases, 479 were in response to Chinese aircraft sightings.