Beijing said it has detained and questioned a Japanese national working on cultural exchange projects for allegedly “endangering China‘s national security”, Japanese newspapers reported Saturday.

The man, who has been missing since mid-July, was identified by the Nikkei business daily as the Japanese head of an organisation working to improve ties between the two rivals.

China said Friday the man was under investigation on suspicion of endangering the country’s national security, Kyodo news agency reported, adding that the allegation was often applied in cases of suspected espionage.

Tokyo said it had been informed by Beijing about a detained Japanese man, but the government’s top spokesman Yoshihide Suga denied Japan was involved in spying “against any nation”.

The suspect, in his late 50s, was due to spend four days in Beijing from July 11 for work, but did not return to Japan and has not been answering his mobile phone, Kyodo said, quoting Japanese government and other sources.

Yoshihide Suga.

There was no immediate response from the Chinese foreign ministry.

Earlier this year Japan denied that it carries out espionage activities abroad as it announced that Chinese authorities had arrested four Japanese citizens on suspicion of spying.

The two countries have been taking steps for more than a year to improve relations that remain plagued by tensions over the legacy of World War II as well as a maritime dispute.

Ties, however, remain shaky and Chinese allegations of spying by Japanese nationals have become a new irritant.

And in April the United States said it was “deeply concerned” after China passed a controversial new law giving police wide-ranging powers over overseas charities.

The law, which comes into force in January, also bans overseas NGOs from recruiting members or raising funds in China and prompted an immediate outcry from charities.

AFP is a global news agency delivering fast, in-depth coverage of the events shaping our world from wars and conflicts to politics, sports, entertainment and the latest breakthroughs in health, science and technology.