Chinese fighter jets 'locked on' to Japanese F-15s

 Chinese military aircraft have locked radar on to Japanese fighter jets over international waters near Japan.

The escalation took place on Saturday near the island of Okinawa, prompting Tokyo to lodge a formal protest with Beijing over what it described as “dangerous” behaviour.

Fire-control radar locks – when one aircraft directs its precise targeting radar on to another – are universally recognised as hostile acts that bring aircraft dangerously close to combat.

The encounters are the most serious direct military confrontations between China and Japan in years.

Relations between Tokyo and Beijing have soured following remarks by Sanae Takaichi, the new Japanese prime minister, that suggested Tokyo could intervene militarily if China attacked Taiwan.

The flare-up has prompted Japan to appeal for more support from the United States, with Ms Takaichi reportedly frustrated with Donald Trump’s silence.

The US president has told his team not to take any action that could jeopardise the trade deal he reached with Xi Jinping in October, the FT reported.

The latest incidents happened on Saturday evening, when Chinese J-15 fighters directed weapons radar at Japanese F-15s flying over international waters.

The Chinese jets had launched from the aircraft carrier Liaoning, which was operating south of the Okinawan islands with three missile destroyers.

“These radar illuminations went beyond what is necessary for the safe flight of aircraft,” said Shinjiro Koizumi, Japan’s defence minister, calling the incidents “regrettable” as well as dangerous.

He added: “We view the occurrence of such an incident with utmost regret, and we have lodged a strong protest with the Chinese side while making a stern demand for measures to prevent any recurrence.”

Japanese fighter jets had been scrambled to monitor Chinese aircraft carrying out take-off and landing drills in the Pacific, Japan’s defence ministry said .

The Japanese jets maintained a safe distance and avoided any moves that could be perceived as provocative, Kyodo News reported, citing defence officials.

During the monitoring, the radar lock happened. No Japanese airspace was violated, and no injuries or damage were reported.

China denied Japan’s account. Col Wang Xuemeng, a Chinese navy spokesman, said Japanese aircraft had repeatedly approached and disrupted Chinese carrier-based flight training that had been announced in advance.

He demanded that Tokyo “immediately stop slandering and smearing and strictly restrain front line actions”.

The radar incidents are the most serious direct military confrontation between China and Japan in more than a decade, signalling Beijing’s willingness to escalate the situation in one of the world’s most militarised regions.

In 2013, Japan accused a Chinese warship of locking radar on a Japanese destroyer. Beijing also denied that incident.

In early November, Ms Takaichi told the Japanese parliament that Japan could respond militarily if a Chinese attack on Taiwan threatened Japanese security.

China, which claims Taiwan as its territory, reacted with fury, urging Chinese citizens not to travel to Japan, suspending seafood import talks and launching a diplomatic offensive against Ms Takaichi.

On Thursday, China deployed more than 100 naval and coast guard vessels across East Asian waters. Taiwan called the build-up a threat to regional stability.

Richard Marles, the Australian defence minister, who met Mr Koizumi in Tokyo on Sunday, said he was “deeply concerned by the actions of China in the last 24 hours”.

Elsewhere in the Pacific, the Philippine coast guard said China fired three flares at a fisheries bureau patrol plane in the South China Sea on Saturday.

Chinese forces often use flares to warn aircraft to move away from what they claim is their airspace over the disputed waters.