A senior Japanese company official in his 50s was detained in Beijing earlier this month for an alleged violation of the country's law, a source familiar with Japan-China relations said Saturday.
The Japanese government has been seeking his release at an early date and trying to provide him with consular support via the Japanese Embassy in Beijing, the source said.
Another source said China has not offered a sufficient explanation as to what led to the detention of the Japanese company official.
China has been stepping up its scrutiny of foreign organizations and individuals in the name of protecting national security, with a number of foreigners held after the introduction of a counterespionage law in 2014 and a national security law in 2015.
Since 2015, at least 16 Japanese nationals, excluding the latest case, have been detained for their alleged involvement in espionage activities.