Riot police walk in the street as a couple kiss on June 15, 2011 in Vancouver, Canada. Vancouver broke out in riots after their hockey team the Vancouver Canucks lost in Game Seven of the Stanley Cup Finals. (Photo by Rich Lam/Getty Images)

Riot police walk in the street as a couple kiss on June 15, 2011 in Vancouver, Canada. Vancouver broke out in riots after their hockey team the Vancouver Canucks lost in Game Seven of the Stanley Cup Finals. (Photo by Rich Lam/Getty Images)

Wounded people walk after clashes with riot police in central Kiev February 18, 2014. Ukrainian riot police advanced on the heart of 12-week-old protests against President Viktor Yanukovich on Tuesday and security forces set a deadline to end disturbances after at least five protesters were reported killed in a day of clashes. (Photo by Vlad Sode/Reuters)

Riot policemen launch tears gas canisters during clashes with coca growers from Yungas in La Paz, Bolivia February 21, 2017. (Photo by David Mercado/Reuters)

Riot police detain a woman during a protest near Mong Kok police station in Hong Kong, China on September 7, 2019. (Photo by Tyrone Siu/Reuters)

A riot policeman fires into the air during clashes with opposition supporters at a rally demanding a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)

A demonstrator confronts riot police during a rally in defense of the nationalization of lithium reserves in the country, in Santiago, Chile on January 29, 2018. (Photo by Pablo Sanhueza/Reuters)

Demonstrators throw fire bombs to riot police during violent protests in central Athens February 12, 2012. (Photo by Milos Bicanski/Getty Images)