The 820th Main Centre for Missile Attack Warning (Russian: Главный центр предупреждения о ракетном нападении (Гцпрн), romanized: GTsPRN[4]) is the Russian Space Forces early warning network against ballistic missile attack.

Other information comes from the early warning Oko and EKS satellites as well as the Don-2N missile defence radar.

The centre also discovers and monitors space objects through the use of radar which are fed into the SKKP network.

[5] The Russian missile warning system originates in the Soviet Union and is often known by its Soviet initials SPRN (СПРН),[1] from Russian: Система предупреждения о ракетном нападении, romanized: Sistema preduprezhdeniya o raketnom napadenii 'Missile attack warning system'.

[3][9] The 1972 Anti-ballistic missile treaty requires that early warning radar stations are located on the periphery of national territory and face outwards.

This will provide China with increased detection range from North pole as well as the Atlantic and Pacific Ocean.

[18] In 1998 SPRN became part of the missile and space defence organisation ракетно-космической обороны (RKO) together with SKKP and the anti-missile troops.