The Defense Ministry is investigating a possible leak of details of a new state-of-the-art missile in a large-scale cyberattack on Mitsubishi Electric Corp, the Asahi Shimbun newspaper reported on Wednesday.

The ministry suspects hackers stole performance requirements that were sent to several defense-industry companies as part of the bidding process for the project, the Asahi reported, citing government sources whom it did not identify. Mitsubishi Electric did not win the bid for the prototype, the newspaper said.

Mitsubishi Electric said it was investigating the report but had no other immediate comment when contacted by Reuters. The Defense Ministry also did not provide an immediate comment.

The missile is of a type in use by countries including the United States, China and Russia, which flies at supersonic speeds over long distances and can pass through enemy missile defense networks to make precision strikes, the newspaper said. Japan has been researching such missiles since fiscal 2018, it said.

Among the leaked details may have been range, propulsion and heat resistance, according to the newspaper.