Japan claimed that a Chinese military aircraft breached its airspace, labeling the incident as “utterly unacceptable” and a threat to national security.

Japan's chief government spokesperson described the alleged incursion as a "serious violation of sovereignty."

"The violation of our airspace by Chinese military aircraft is not only a serious violation of our sovereignty but also a threat to our security and is totally unacceptable," Yoshimasa Hayashi stated on Tuesday.

He added, "We understand that this is the first confirmed and announced airspace incursion by a Chinese military aircraft since we started the anti-airspace incursion measures.

“We refrain from giving a definite answer as to the intended purpose of the Chinese aircraft’s action. However, China’s recent military activities near Japan have a tendency to expand and become increasingly active", he stressed.

“The government will continue to pay close attention to China’s military activities and will take all possible measures to ensure vigilant surveillance and airspace violation measures,” he said.

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A Y-9 surveillance aircraft entered Japanese airspace for approximately two minutes starting at 11:29 am on Monday, according to Japan's Defense Ministry.

The ministry indicated that the aircraft "violated territorial airspace near the Danjo Islands in Nagasaki Prefecture," prompting Japan to urgently scramble fighter jets.

While the ministry claimed that "warnings" and other measures were issued to the aircraft, public broadcaster NHK mentioned that no weapons, such as flare guns, were deployed.

The Japanese Defense Ministry published a photograph of what it identified as the plane, which allegedly circled over waters southeast of the islands several times before and after entering Japan's airspace, according to Kyodo News. The aircraft returned to China at approximately 1:15 pm.

Japan's Deputy Foreign Minister Masataka Okano summoned China's acting ambassador late Monday to issue a "firm protest" and demanded preventive measures to avoid a recurrence, the Foreign Ministry announced.

The Chinese diplomat responded by stating that the issue would be reported to Beijing, according to the ministry. Beijing has yet to issue an official comment.

It is worth noting that China views the increased US cooperation with Japan as a significant threat. The growing military collaboration, including joint operations and arms industry cooperation, reinforces China's apprehensions about a stronger, more integrated US-Japan alliance that could aid the US in its regional ambitions. 

China has urged Japan to contribute constructively to maintaining and promoting peace, stability, and development, rather than acting as a "vanguard" for Western expansion into the Asia-Pacific region.

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