TOKYO — Japan is investigating a possible leak of data including details of a prototype missile in a massive cyberattack earlier this year on Mitsubishi Electric Corp., officials said Wednesday.
The suspected leak involves sensitive information about a prototype of a cutting-edge high speed gliding missile intended for deployment for the defense of Japan's remote islands amid China's military assertiveness in the region.
Chief Cabinet Secretary Yoshihide Suga told reporters that the Defense Ministry is investigating "the possible impact of the information leak on national security."
Suga declined to give further details.
The Defense Ministry has been studying a prototype missile known as HGV, which flies at supersonic speeds and is also being developed by the U.S., China and Russia.
The ministry suspects the information might have been stolen from documents sent from several defense equipment makers as part of a bidding process for the project, Mitsubishi Electric did not win the bid, Japanese media reports said.
Mitsubishi said in a statement Wednesday that it had reported to the Defense Ministry in February a possible leak of sensitive information related to a cyberattack earlier this year. Mitsubishi has acknowledged that its personal data on some 8,000 people also might have been leaked.
The company said it is continuing to cooperate with in the investigation, while pledging to step up its information security.
Several other Japanese defense contractors, including NEC Corp. , Pasco Corp. and Kobe Steel Ltd., were also hit by cyberattacks this year.