Anti-Donald Trump sentiment prompted three fights in the first nine seconds of a hockey game between the United States and Canada on Saturday, 15 February.
Canadian fans booed the US national anthem "The Star-Spangled Banner" as well as when the American players were introduced.
It came after the US president's repeated calls for Canada to become the 51st US state, effectively erasing the 5,525-mile border between the two nations, and his threat of major tariffs against the country.
Fans in Canada have booed the US anthem at NHL and NBA games since these remarks.
