Putin gave a short speech in Russian to cheers from the Canadian crowd, saying "Thank you very much, hope to meet you in the (men's hockey) final."
A cluster of American and Canadian students later excitedly shared stories about their chance encounter with Russia's leader.
"I got to shake his hand!" said Daniel Saltman of Los Gatos, California.
Medical student Hannah Glinter of Winnipeg, Canada, said she followed him into Canada House, slipping in behind his bodyguards.
"He's not nearly as scary as I thought he would be. But his security is quite scary," Glinter said. "I can't speak for his personality whatsoever, but he shook my hand twice, so he must be friendly."
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