Flames from a burning barricade lit by pro-democracy protesters is reflected in the windows of a passing bus as passengers watch on during a protest gathering in front of Mong Kok police station on September 22, 2019 in Hong Kong, China. Pro-democracy protesters have continued demonstrations across Hong Kong, calling for the city's Chief Executive Carrie Lam to immediately meet the rest of their demands, including an independent inquiry into police brutality, the retraction of the word “riot” to describe the rallies, and genuine universal suffrage, as the territory faces a leadership crisis. (Photo by Chris McGrath/Getty Images)

An opposition activist clashes with the police during a march against Venezuelan President Nicolas Maduro held on May Day, in Caracas on May 1, 2017. Security forces in riot vans blocked off central Caracas Monday as Venezuela braced for pro- and anti- government May Day protests one month after a wave of deadly political unrest erupted. (Photo by Federico Parra/AFP Photo)

Chinese soldiers leave after Chinese President Xi Jinping inspected troops of People's Liberation Army (PLA) Hong Kong Garrison at the Shek Kong Barracks in Hong Kong, Friday, June 30, 2017. Xi landed in Hong Kong Thursday to mark the 20th anniversary of Beijing taking control of the former British colony, accompanied by a formidable layer of security as authorities showed little patience for pro-democracy protests. (Photo by Kin Cheung/AP Photo)

A pro-Russian supporter with the Russian national flag on her shoulders takes part in a meeting in Simferopol, March 6, 2014. Crimea's parliament voted to join Russia on Thursday and its Moscow-backed government set a referendum within 10 days on the decision in a dramatic escalation of the crisis over the Ukrainian Black Sea peninsula. (Photo by Vasily Fedosenko/Reuters)

Tim Anderson final balanced rock stack in the Llano River. Tim Anderson, rock balancing “pro” from Pennsylvania, carefully worked to balance his stack on a dry spot in the Llano river Saturday March 12, 2016. He was an honored guest of the festival and enjoyed visiting Texas so he came for another year. The river was higher this year because of the rains so the balancers could not get to the better rock that were available last year. (Photo by Nell Carroll/American-Statesman)

Civilians are led by members of pro-Russian self-defence units as they run outside a military base during an assault in the Crimean town of Belbek near Sevastopol March 22, 2014. Russian troops forced their way into a Ukrainian airbase in Crimea with armored vehicles, automatic fire and stun grenades on Saturday, injuring a Ukrainian serviceman and detaining the base's commander for talks. (Photo by Vasily Fedosenko/Reuters)

Figurines of former pro-Russian separatist commander Igor Strelkov from the collection entitled “Toy Soldiers of Novorossiya” are on display at a workshop in Moscow August 29, 2014. A Moscow-based maker of toy soldiers has sought inspiration for his creations from Ukrainian rebels fighting government troops in the east of Ukraine. Toy soldier maker, Timur Zamilov, displayed his new collection of rebel fighters cast in metal on Friday, before they are due to go on sale. His new collection is entitled “Toy Soldiers of Novorossiya” (New Russia), a reference to regions in eastern Ukraine where pro-Russian separatist fighters want full independence. Zamilov's selection includes models of Cossack soldiers, volunteers, soldiers bearing anti-aircraft missiles and even a miniature of prominent rebel leader Igor Strelkov. (Photo by Sergei Karpukhin/Reuters)

South Korean soldiers participate in a winter river crossing operation in preparation for a possible North Korean attack on February 8, 2012 in Yeoju, South Korea. The Korean peninsula is the world's last Cold War frontier as stalinist North Korea and pro-western South Korea have been technically at war since the 1950-53 conflict. (Photo by Chung Sung-Jun/Getty Images)