A Colombian Nukak Maku Indian boy gestures in a refugee camp at Agua Bonita near San Jose del Guaviare of Guaviare province September 3, 2015. Since emerging from the jungle in 2005, half naked and carrying blowpipes, the Nukak have lived in settlements near the frontier town of San Jose del Guaviare, a humid outpost in the Amazon 400 km (250 miles) southeast of the capital Bogota. (Photo by John Vizcaino/Reuters)

Two carnival revellers masquerade as Leonardo da Vinci's painting “Mona Lisa” pose in St. Mark's Square in Venice, Italy, Sunday, January 31, 2016. Carnival-goers in Venice are being asked by police to momentarily lift their masks as part of new anti-terrorism measures for the annual festivities. (Photo by Domenico Stinellis/AP Photo)

South Korean rescue members wearing chemical protective suits walk past a monster character (R) during an anti-terror drill as part of a disaster management exercise at the COEX shopping and exhibition center in Seoul on May 20, 2016. South Korea is holding its 2016 Safe Korea anti-disaster exercise this week against terrorist threats and natural disasters. (Photo by Jung Yeon-Je/AFP Photo)

Members of the South Korean Special Weapons and Tactics team exhibit their skill during anti-terrorism exercises at a training camp on May 30, 2005 in Seoul, South Korea. (Photo by Chung Sung Jun/Getty Images)

Colombian police help carry people's household belongings across the Tachira River from Venezuela, top, to Colombia, on the border that separates San Antonio del Tachira, Venezuela from Villa del Rosario, Colombia, Tuesday, August 25, 2015, during a mass exodus of Colombians. Venezuelan President Nicolas Maduro vowed to extend a crackdown on illegal migrants from neighboring Colombia he blames for rampant crime and widespread shortages, while authorities across the border struggled to attend to droves of returning deportees. (Photo by Eliecer Mantilla/AP Photo)

A model wears a creation by Inmaculada Martinez on the backstage, during the International Flamenco Fashion Show SIMOF in the Andalusian capital of Seville, Spain February 8, 2019. (Photo by Marcelo del Pozo/Reuters)

Maria, 18, wearing a traditional Sevillana outfit, poses for a portrait during the traditional Feria de Abril (April fair) in the Andalusian capital of Seville April 16, 2013. (Photo by Marcelo del Pozo/Reuters)

The Chavo del Ocho balloon makes its way along the streets during an annual Christmas parade at Santiago town in Chile, December 13, 2015. (Photo by Pablo Sanhueza/Reuters)