On 6 and 13 December , the Soviet Navy dispatched two groups of cruisers and destroyers and a submarine armed with nuclear missiles from Vladivostok ; they trailed US Task Force 74 into the Indian Ocean from 18 December 1971 until 7 January 1972 .
On 6 December and 13 December , the Soviet Navy dispatched two groups of cruisers and destroyers and a submarine armed with nuclear missiles from Vladivostok ; they trailed U.S. Task Force 74 into the Indian Ocean from 18 December 1971 until 7 January 1972 .