Watch as Canadians BOO the US national anthem: 'This is unheard of!'

Canadian Hockey fans have expressed their discontent by booing as The Star-Spangled Banner played ahead of the Ottawa Senators game against the Minnesota Wild on Saturday night.

This comes after the US president Donald Trump signed an order Saturday to impose stiff tariffs on imports from Canada, Mexico, and China, which drew swift retaliation and sparked a trade war between the neighbouring country.

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