Viktor Ivanov, the head of Russia's Federal Drug Control Service, said the amount of heroin seized in the operation was significant, the Russia news agency RIA Novosti reported.
"Twenty-one tons is, in essence, the annual volume of drugs brought into Russia," Ivanov said.
Official statistics indicate some 30,000 Russians die from heroin abuse each year with non-governmental organizations estimating the country has as many as 3 million heroin addicts.
The vast majority of heroin consumed in Russia comes from Afghanistan.
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