A court in Beijing on Tuesday sentenced a Japanese man convicted of spying to six years in prison, according to sources familiar with Sino-Japanese relations.

The court also ordered Hideji Suzuki, the head of a Japan-China youth exchange association, to pay a fine of 50,000 Chinese yuan (approximately ¥800,000).

Detained in July 2016 while visiting Beijing to make arrangements for a symposium, he was formally arrested in February 2017 and indicted in June that same year.

Suzuki has an extensive history of visiting China, where he engaged in activities such as afforestation. He also interacted actively with Communist Party officials in international exchanges, and had been commended for his efforts to promote Sino-Japanese friendship.

Since 2015 at least nine Japanese have been indicted in China for alleged involvement in spying activities, and this marks the eighth time court's have rendered verdicts in such cases.

The remaining case involves a male employee of major Japanese trading house Itochu Corp. who was detained during a visit to Guangzhou in February 2018 on suspicion of harming national security.

On Monday, a court in the southern province of Hainan sentenced a Japanese man to 15 years in prison for illegally obtaining state secrets, analyzing them and disseminating them abroad.

His Japanese colleague was sentenced last Friday by a court in Shandong Province to a prison term of five years and six months.

The two were among six Japanese who were detained in 2017 while conducting geological assessments of potential hot spring development sites in Hainan and Shandong. The others were allowed to return to Japan.

The detentions of Japanese nationals come as Chinese leadership under President Xi Jinping has stepped up monitoring of foreign groups and individuals working inside China.