US Expresses Concern About New Cyberattacks in Japan

The United States gave a stern warning over recent cyberattacks on Japan’s biggest defense contractors, the latest in a series of security breaches that have fueled concern about Tokyo’s ability to handle delicate information.

An online assault on defense contractors including Mitsubishi Heavy Industries, which builds F-15 fighter jets and other American-designed weapons for Japan’s Self-Defense Forces, began in August, but only came to light this week, prompting rebukes from Japanese officials over the timing of the disclosure. The IHI Corporation, a military contractor that supplies engine parts for fighter jets, may have also been a target, the Nikkei business daily reported. The breach came less than two weeks after a Japanese air traffic controller was questioned for posting secret American flight information on his blog. The data including detailed flight plans for Air Force One last November, as well as data on an American military reconnaissance drone, officials said. The breaches threaten to undermine any progress made by Japan, an important American ally, in bolstering cybersecurity in recent years.