Moscow (CNN) At first glance, it looked like an episode from nineteenth-century Russian novel: A general challenging his opponent to a duel. In reality, it was direct threat to Russian President Vladimir Putin's domestic political opposition.

On Tuesday, Russia's National Guard chief, Viktor Zolotov, released a YouTube video challenging opposition leader Alexei Navalny to a duel, calling the anti-corruption activist a "scoundrel," and threatening to turn him into a "tenderized beefsteak."

The video, nearly seven minutes long, was posted on the official YouTube channel of Russia's National Guard. Zolotov, appearing in uniform and wearing an officer's peaked cap, addressed the activist directly and with barely contained anger in his voice.

"You have made me the subject of insulting, defamatory remarks," Zolotov said. "You know, it is not customary among officers simply to forgive. From time immemorial, scoundrels have had their faces smashed and been called to duels."

Addressing the activist as "Mr. Navalny," Zolotov continued: "No one is stopping us from reviving at least some of these traditions, by which I mean seeking satisfaction. I challenge you to single combat — in the ring, on the judo mat, wherever, and I promise to make juicy, tenderized meat out of you."

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