In this September 27, 2017 file photo, girls walk past a wall riddled with bullet holes from shootings between rival drug traffickers, at the Rocinha slum, in Rio de Janeiro, Brazil. Violence is on the rise in Rio's slums after several years of decline, and the killings of kids have shocked even residents long inured to deaths from gangs and police. (Photo by Silvia Izquierdo/AP Photo)

Japan' s Kaori Sakamoto competes in the women' s single skating short program of the figure skating event during the Pyeongchang 2018 Winter Olympic Games at the Gangneung Ice Arena in Gangneung on February 21, 2018. (Photo by John Sibley/Reuters)

A minaret, that was damaged during fighting between Islamic State jihadists and government forces, is seen in Ben Guerdane, near the Libyan border, Tunisia April 10, 2016. After a U.S. air strike killed a Tunisian jihadist commander in western Libya in late February, dozens of Islamic State fighters sneaked across the border into Tunisia and attacked an army barracks and police bases in the town of Ben Guerdane. (Photo by Zohra Bensemra/Reuters)

The Invasion. A quiet street in Macau. Modernization around is quickly changing the city, as documented by Paul Tsui. (Photo by Paul Tsui/National Geographic Travel Photographer of the Year Contest)

A boy plays on the glass at Thailand's first skywalk in Bangkok, Thailand on November 18, 2018. (Photo by Soe Zeya Tun/Reuters)

Principal of the Royal Ballet, Natalia Osipova, performs outside the Edinburgh International Conference Centre in Edinburgh, England on November 21, 2018, where she is starring in the new contemporary ballet “The Mother”. (PHoto by Jane Barlow/PA Wire via ZUMA Press)

Pfc. Remy Bouchard swaps a cigarette for an egg with a French Orphan near La Haye Du Puits, France on July 18, 1944, which was captured by American forces. The boy is only twelve years old. (Photo by Hugh Broderick/AP Photo)

Culinary Specialist 2nd Class Jaqueline Rodriguez subdues a simulated suspect after being sprayed with oleoresin capsicum (OC) spray during security training aboard the amphibious dock landing ship USS Comstock (LSD 45). (U.S. Navy photo by Mass Communication Specialist 2nd Class Joseph M. Buliavac/Released). May 10, 2011