WASHINGTON/TOKYO—The Pentagon said on Tuesday it was confident about sharing intelligence with Japan, despite a U.S. news report saying Chinese military hackers gained access to Japan’s most sensitive defense networks.
On Monday, the Washington Post cited unnamed current and former U.S. and Japanese officials as saying that Chinese military hackers gained access to Japan’s classified defense networks in 2020, accessing information about the U.S. ally’s military capabilities, plans, and assessments of shortcomings.
Japan’s Chief Cabinet Secretary Hirokazu Matsuno told a regular press briefing on Tuesday Japan could not confirm whether any security information had been leaked.
The Post quoted one former U.S. military official as saying the breach was “bad—shockingly bad” and that the head of the U.S. National Security Agency flew to Tokyo to brief the Japanese defense minister, who asked the U.S. officials to alert the prime minister.
The paper said Japan had taken steps to strengthen its networks, but cited unnamed officials as saying that these were still deemed not sufficiently secure from spying by China, which could impede greater intelligence sharing between the Pentagon and Japan’s Defense Ministry.
A Pentagon spokesperson, Sabrina Singh, declined to comment on the Post report, saying it would let Tokyo speak for its intelligence and cyber capabilities, but added: “We feel confident in our relationship and the intelligence sharing that we do with Japan and we’re confident that we will continue that.”
The U.S. National Security Agency did not immediately respond to a request for comment on the Post report, which comes ahead of a trilateral summit between the United States, Japan and South Korea on Aug. 18, at which the three allies are expected to announce plans to step up security cooperation in the face of increasing concerns about China.
Asked about the Post report, Japan’s Chief Cabinet Secretary Matsuno said Japan and the United States have always been in close communication on various levels, and added:
“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.”
Matsuno said cyber security was the foundation for maintaining the Japan–U.S. alliance, and Japan would continue to work to keep its network firm and secure.
There was no immediate comment from Beijing.
