A Japanese man in his 50s was sentenced to 12 years in prison in China earlier this month for espionage, a Japanese Foreign Ministry source said Thursday.

The man, who has been detained in Changsha in central China's Hunan Province since July 2019, was given the sentence by an intermediate court in the city on Feb. 8, but the ruling did not provide details of his spying activities, according to the source.

The man could appeal the court decision. The Japanese government has been calling on China to release him at an early date and ensure transparency in judicial procedures related to his case, the source said.

Since 2015, at least 16 Japanese citizens have been detained in China on such charges as espionage. Of them, 10 nationals including the man in his 50s have been sentenced to jail terms of up to 15 years.

China has been stepping up its scrutiny of foreign organizations and individuals in the name of protecting national security, with a number of foreigners detained particularly after a counterespionage law took effect in 2014 and a national security law in 2015.

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