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In page Cuban Missile Crisis:

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The first consignment of Soviet R-12 missiles arrived on the night of 8 September, followed by a second on 16 September. The R-12 was a medium-range ballistic missile capable of carrying a thermonuclear warhead.[15] It was a single-stage, road-transportable, surface-launched, storable liquid propellant-fuelled missile that could deliver a megaton-class nuclear weapon.[citation needed] The Soviets were building nine sites, six for R-12 medium-range missiles (NATO designation SS-4 Sandal) with an effective range of 2,000 kilometres (1,200 mi) and three for R-14 intermediate-range ballistic missiles (NATO designation SS-5 Skean) with a maximum range of 4,500 kilometres (2,800 mi).[16]