A Japanese man was sentenced Wednesday to three and a half years in prison in China on espionage charges, according to the Japanese embassy in Beijing.

The embassy did not identify the man, who has been detained since March 2023. Japan’s Kyodo News Agency described him as a man in his 60s and an employee of Astellas Pharma Inc., a major Japanese pharmaceutical company.

The man was charged with espionage in August and his first hearing was held in November but no details were released.

The Beijing No. 2 Intermediate People’s Court did not immediately make an announcement after handing down the sentence.

Kenji Kanasugi, the Japanese ambassador to China, called the sentencing “extremely regrettable.” The Japanese government has protested a series of detentions of its citizens in China.

A total of 17 Japanese citizens with business or other connections to China have been detained since 2014, when China enacted the anti-spying law. Five remain in China, Kyodo reported. A Japanese diplomat was detained for questioning in 2022 and released hours later, prompting strong protests from Japan.

Kanasugi was present at Wednesday’s ruling, but Japanese reporters were not allowed inside the courtroom. He told reporters that Japan has and will continue to demand the early release of Japanese nationals in detention, adding that such detentions are “one of the biggest obstacles to improving people-to-people exchanges and public sentiment between Japan and China.”

A statement released by the Japanese embassy in Beijing urged the Chinese government to ensure the humane treatment of detainees and to improve the transparency of the judicial process.

Japan considers China’s growing influence in the region as a threat to its national security and economy, and the risks of getting caught in China on espionage allegations are a growing concern in Japan, including its business community. A safety handbook for visitors to China, published by the Japanese embassy in Beijing, urges visitors to use extra caution.

—AP