China is expected to soon decide whether to formally arrest a Japanese businessman who has been detained in Beijing since March on suspicion of espionage, sources familiar with the bilateral relationship said Wednesday.

The Chinese government recently notified Tokyo that local authorities had placed the Japanese national under criminal detention. Chinese law provides for up to 37 days of criminal detention before a decision on formal arrest is made.

Beijing has not responded to Tokyo's repeated requests to quickly release the employee of drugmaker Astellas Pharma Inc.

His prolonged detention could further worsen Sino-Japanese ties already strained over the release of treated radioactive water from the crippled Fukushima nuclear power plant into the sea from late August.

Staff at the Japanese Embassy in Beijing recently met the man and confirmed he had no health issues, Japanese government officials said. The embassy has been in contact with his family and is helping them with communication with the man.

Chinese Foreign Ministry spokeswoman Mao Ning said at a press conference Wednesday she is not aware of the Japanese citizen's situation, adding Beijing will treat his case in accordance with the law and protect his legitimate rights.

The senior Astellas Pharma employee was detained in March, shortly before his planned return to Japan. It remains unknown how he allegedly violated the counterespionage law and criminal code in China.

In April, then Japanese Foreign Minister Yoshimasa Hayashi strongly demanded the man's early release in his talks with Premier Li Qiang and other senior Chinese officials during a trip to Beijing.

In July, the Japanese embassy was granted in-person consular access to the businessman for the first time. Previously, the Chinese government had only allowed monthly consular access to him via video link, citing the need to prevent the spread of COVID-19.

On July 1, a revised counterespionage law took effect in China, broadening the scope of what constitutes spying activities.

Since the country's counterespionage law first came into force in November 2014, 17 Japanese citizens have been detained for alleged involvement in spying activities. Five of them are still being held, according to the Japanese government.

==Kyodo

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