BEIJING - There have been continuous harassment and provocation targeting China's diplomatic missions in Japan, the Chinese Foreign Ministry said on Friday, urging Japan to reflect on, thoroughly investigate, implement corrective measures and fully account for such incidents.

A series of grave offenses have occurred recently, such as the embassy break-in committed by a Self-Defense Forces (SDF) lieutenant carrying a knife, spokesperson for the ministry Guo Jiakun said at a regular news briefing.

He also stressed that the entry of an SDF vessel into the Taiwan Strait severely threatens China's sovereignty and security, and China firmly opposes it and has lodged strong protest with Japan.

The Chinese military has handled the entry in accordance with laws and regulations, the spokesperson said.

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Noting that Japanese Prime Minister Sanae Takaichi's erroneous remarks on Taiwan have already inflicted serious damage on China-Japan relations, Guo said Japan's dispatch of the SDF vessel into the Taiwan Strait to brandish its military might and engage in deliberate provocation is compounding the error.

"It once again exposes the dangerous attempt of certain individuals in Japan to militarily interfere in the Taiwan Strait and undermine peace and stability across the Strait," Guo said, adding that these moves also severely damage the political foundation of China-Japan relations.

The spokesperson stressed that the Taiwan question bears on China's sovereignty and territorial integrity, as well as the political foundation of China-Japan relations, and it constitutes a red line that must not be crossed.

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China once again urges the Japanese side to earnestly reflect on its mistakes, pull back from the brink, exercise prudence in its words and actions, and refrain from going further down the wrong path, Guo said.