A demonstrator uses a slingshot during a protest against Chile's government in Santiago, Chile, November 14, 2019. (Photo by Jorge Silva/Reuters)

Women members of the national police take part in a parade during a graduation ceremony in Bogota, Colombia on November 7, 2019. (Photo by Juan Barreto/AFP Photo)

A performer takes part in the annual street parade, which is part of the Carnival of Cultures celebrating the multi-ethnic diversity of the city, in Berlin, Germany on May 20, 2018. (Photo by Hannibal Hanschke/Reuters)

Ammunition airlift into besieged Khe Sanh, Operation Pegasus, April 1968. (Photo by Larry Burrows/AP Photo)

Two Girls who managed to evade the police walk away as police on foot and horseback push back to te curd at Park Row, In New York on April 26, 1960, A milling throng of more than 1,000 High students who storned city hall in a Demonstration supporting teachers wage demands. (Photo by AP Photo)

Migrants with a stick, stones and knife fight with each other after a brawl erupted over a place in an overcrowded train heading to the Serbian border at the train station in Gevgelija, The Former Yugoslav Republic of Macedonia, 14 August 2015. (Photo by Georgi Licovski/EPA/EFE)

Colombia' s Caterine Ibarguen competes in the women' s long jump during the 2018 IAAF Birmingham Diamond League athletics meeting at Alexander Stadium in Birmingham on August 18, 2018. (Photo by Peter Cziborra/Action Images via Reuters)

Hollydell Poseidon ridden by Madeline Reader-Smith takes part in the Shetland Pony Grand National Flat Race in Aid of Bob Champion Cancer Trust during day two of the Cambridgeshire Meeting at Newmarket Racecourse on Friday, September 28, 2018. (Photo by Mike Egerton/PA Wire)