China and Russia carried out a joint aerial patrol over the western Pacific on Wednesday, the Chinese Defense Ministry said, a day after their bombers flew together over the Sea of Japan and the East China Sea.
The series of joint flights held amid increased military cooperation between Beijing and Moscow stirred worries in Tokyo, with Chief Cabinet Secretary Hirokazu Matsuno calling them "a grave security concern" as they are intended to be "a clear show of force" toward Japan.
On Tuesday, Japan's Air Self-Defense Force scrambled fighter jets in response to four Chinese and Russian bombers jointly flying above waters near Japan.
While Japan's airspace was not violated, the Japanese Defense Ministry conveyed its grave concerns to China and Russia through diplomatic channels.
The Global Times, a tabloid affiliated with China's ruling Communist Party, quoted Wei Dongxu, a Beijing-based military expert, as saying Tuesday that the China-Russia joint patrol serves as "a powerful counterbalance" when U.S.-led "continued provocations" have severely disrupted regional peace and stability.
In March, Chinese President Xi Jinping and his Russian counterpart Vladimir Putin agreed in their talks in Moscow to regularly hold joint military drills and patrols between their countries' navies and air forces.