TOKYO — Japan cannot confirm if any security information has been leaked, the top government spokesperson said on Tuesday when asked about a Washington Post report on Chinese hacking into its defense cyber networks.

Chinese military hackers gained access to a classified defense network in Japan beginning in 2020, accessing information about the US ally’s military capabilities, plans and assessments of shortcomings, the Washington Post reported on Monday, citing senior officials.

Upon hearing about the incident, the heads of the US National Security Agency flew to Tokyo to brief the Japanese defense minister, who asked the US officials to alert the prime minister themselves, the newspaper report said.

Speaking at a regular press briefing on Tuesday, Japan’s Chief Cabinet Secretary Hirokazu Matsuno said Japan and US have always been in close communication on various levels.

“Due to the nature of the matter, I am unable to provide further details of the communication but we haven’t confirmed the fact that security information has been leaked due to cyber attacks,” he said.

There was no immediate comment from Beijing.

Mr. Matsuno also said that cyber security is the foundation for maintaining the Japan-US alliance, and that Japan will continue to work to keep its network firm and secure.

Meanwhile, Japan’s slow response to improve its cyber network could impede greater intelligence sharing between the Pentagon and Japan’s Defense Ministry, the Washington Post said, citing officials. — Reuters