The Japanese government demanded the swift release of one of its citizens detained in Iran for over a month on Wednesday, without providing further details of the case.
The person was detained on January 20 and the government has been in touch with the family and the Iranian authorities, Deputy Chief Cabinet Secretary Masanao Ozaki told reporters. He declined to identify the person or give any other details of the incident.
Radio Free Europe earlier reported that Shinnosuke Kawashima, the Tehran bureau chief of Japan's public broadcaster, NHK, had been arrested by Iran and transferred to a Tehran prison.
NHK declined to confirm that an employee of theirs had been detained.
"As NHK, we always act with the safety of our staff as the top priority. There is nothing we can answer at this stage," a spokesperson said.
The NHK World website identifies Kawashima as an international affairs correspondent who worked as the broadcaster's bureau chief in Jakarta, Indonesia from 2017.
A LinkedIn account using his name said he joined NHK in 2005.