North Korean cybercriminals broke into a leading Russian missile manufacturer’s systems last year, new research revealed Monday, in an apparent attempt to steal classified information to advance its own weapons development.

Cybersecurity firm SentinelOne reported that notorious DPRK threat groups ScarCruft and the Lazarus Group carried out the intrusions against Russia’s missile design bureau NPO Mashinostroyeniya between late 2021 and May 2022, exploiting backdoors and compromising an email server to gain access to the company’s systems.