Hackers associated with the ruling regime of North Korea breached the computer networks of a missile developer in Russia, according to Reuters, despite the outwardly friendly relations between the two countries. According to Reuters, the cyber teams known as ScarCruft and Lazarus managed to raid the networks of NPO Mashinostroyeniya, a rocket design company based near Moscow. It’s not clear if any data was taken during the hack or what the hackers viewed, though North Korea has been working to build an intercontinental ballistic missile (ICBM) capable of hitting the mainland United States. The hack was discovered when an employee of NPO Mash—which has pioneered the development of Russia’s hypersonic missiles and other technologies—accidentally publicly leaked his company’s internal communications while attempting to investigate the hack. “How the information was exposed was an absolutely hilarious screwup,” computer security expert Nicholas Weaver told Reuters.