As Russia inches towards the deployment of hypersonic missiles, it is becoming increasingly paranoid about leaks of secrets from prominent Russian scientists.

“Hypersonic” stands for speeds greater than Mach 5 (five times the speed of sound). Recently developed Russian missiles include ballistic air-launched, nuclear-capable Mach-8 Zircon and Mach-10 Kinzhal (Dagger) designed to target aircraft carriers, as well as the Mach-27 Avangard glide vehicle that separates from an intercontinental ballistic missile and carries a two-megaton nuclear yield. High speed and maneuverability of hypersonic vehicles reduce the effectiveness of countermeasures.