Sjinkie Knegt of Netherlands, left, and Park Se-Yeong of South Korea crash out as they compete in a men's 1500m short track speedskating final at the Iceberg Skating Palace during the 2014 Winter Olympics, Monday, February 10, 2014, in Sochi, Russia. (Photo by Bernat Armangue/AP Photo)

Serge Huguenin of the Blondeau foundry takes the newly melted bell out of the mould in La Chaux-de-Fonds, Switzerland January 21, 2016. At this year's Summer Olympics in Rio de Janeiro, no matter how elaborate the opening ceremony or how sophisticated the live broadcasts, the final lap of athletics races will be announced the traditional way by ringing an old-fashioned bell. Omega, the official timekeeper of the event, has ordered 21 bells, forged almost entirely by hand by Blondeau's Bell Foundry in the Jura Mountains in Switzerland. Each last-lap bell is branded with the RIO 2016 logo and circled with the words “2016 GAMES OF THE XXXI OLYMPIAD”. (Photo by Denis Balibouse/Reuters)

Fans of Chris Mazdzer of the United States including his girlfriend Mara Marian (C) react following his third run during the Luge Men's Singles on day two of the PyeongChang 2018 Winter Olympic Games at Olympic Sliding Centre on February 11, 2018 in Pyeongchang-gun, South Korea. (Photo by Alexander Hassenstein/Getty Images)

An environmental activist performs during a protest in front of the headquarters of Brazilian mining company Vale SA in downtown Rio de Janeiro, Brazil, November 16, 2015. The collapse of two dams at a Brazilian mine, owned by Vale SA and BHP Billiton Ltd, has cut off drinking water for quarter of a million people and saturated waterways downstream with dense orange sediment that could wreck the ecosystem for years to come. Nine people were killed, 19 are still listed as missing and 500 people were displaced from their homes when the dams burst at an iron ore mine in southeastern Brazil on November 5. (Photo by Sergio Moraes/Reuters)

In this July 11, 2016 photo, a young, masked drug trafficker poses for photos holding his guns at a slum in Rio de Janeiro, Brazil. Teenagers openly tote guns while they work as guards, lookouts and distributors for drug lords operating just a few miles from where hundreds of thousands and tourists and athletes will be for the Aug. 5-21 Olympic Games. (Photo by Felipe Dana/AP Photo)

A child, from Municipal school Parana, poses during the project “Fencing School” in Rio de Janeiro, Brazil, March 30, 2016. Children in Rio de Janeiro lift their sights and their swords to new idols, as a round of fencing workshops takes to public schools. The International Fencing Federation, together with the Brazilian and state federations, will reach 40 public schools in March and April. The aim is to whip up a following for the Olympic sport, little known in the soccer-mad nation, as Rio sets the stage for the Summer Games in August. (Photo by Sergio Moraes/Reuters)

Members of a samba school warm up before parading along Copacabana Beach in Rio de Janeiro, Brazil, Saturday, January 6, 2018. Musicians and members from Rio de Janeiro's top 13 samba schools have paraded in an event aimed at promoting tourism ahead of Rio's world famous Carnival that begins early next month. (Photo by Leo Correa/AP Photo)

A policeman is pictured near a woman with a baby during an operation against drug dealers in Cidade de Deus or City of God slum in Rio de Janeiro, Brazil, November 23, 2016. (Photo by Ricardo Moraes/Reuters)