Photo/Illutration Yuan Chengji, center, calls for the release of his father, Yuan Keqin, a former professor at the Hokkaido University of Education who was detained by Chinese authorities. Chengji talks to reporters on May 25, 2021, at the Hokkaido government office in Sapporo. (Ichiro Matsuo)

A former professor at the Hokkaido University of Education who had been detained by Chinese authorities for years was sentenced to prison in January for espionage, his supporters announced.

Yuan Keqin, a Chinese national, was sentenced to six years in prison by a court in Jilin province for violating the anti-espionage law.

Yuan was detained in 2019 when he returned to China temporarily while still working for the Japanese university. The Chinese Foreign Ministry later announced that he had been indicted.

Yuan graduated from a university in China before completing the doctoral program at the Graduate School of Hitotsubashi University in Tokyo.

At the Hokkaido University of Education, he studied and taught East Asian politics. He officially retired from the university in March 2021, while still detained in China.

A group consisting of Yuan’s family and fellow researchers has been calling for his release, insisting that he is innocent. The support group said it will hold a news conference as soon as it has more details about the verdict.

China’s Foreign Ministry declined to comment on Yuan’s situation.

“I will defer to the relevant authorities to provide the specifics,” said ministry spokesman Wang Wenbin on May 14. “What I can tell you is that China is a country under the rule of law and handles the relevant case in accordance with the law.”