Children play in an outdoor shower as a soldier takes part in a surprise operation in the Manguinhos slum in Rio de Janeiro, Brazil, Thursday, January 18, 2018. Troops have been sent to Rio due to the increase of the violence, and in an attempt to help restore order, but so far have had little impact. The operation on Thursday took place three weeks ahead of Carnival, when thousands of tourists are expected to arrive in the city. (Photo by Leo Correa/AP Photo)

Soldiers stand guard in Maua square where a cotton candy vendor passes by in Rio de Janeiro, Brazil, Saturday, July 9, 2016, as security is deployed to get to know the areas they'll be patrolling during the Olympics. Roughly twice the security contingent at the London Olympics will be deployed during the August games in Rio, which are expected to draw thousands of foreigners to a city where armed muggings, stray bullets and turf wars between heavily armed drug gangs are routine. (Photo by Leo Correa/AP Photo)

Men rest after salvaging metal on the 30th floor of the “Tower of David” skyscraper in Caracas February 3, 2014. A 45-storey skyscraper in the center of Venezuela's capital Caracas is a slum, probably the highest in the world. Dubbed the “Tower of David”, the building was intended to be a shining new financial center but was abandoned around 1994 after the death of its developer – banker and horse-breeder David Brillembourg – and the collapse of the financial sector. (Photo by Jorge Silva/Reuters)

Boards stand lined up at the Rocinha Surf Association, ASR, headquarters at Rocinha slum in Rio de Janeiro, Brazil, Thursday, July 2, 2015. ASR has given free lessons to over 2,000 children from Rio's shantytowns in the hopes of keeping the boys, who are mostly in their early teens and a few girls occupied by the sport and off the streets. (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)

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)

Alessandra Perilli, of San Marino, competes during the trap women's qualification at the 2016 Summer Olympics in Rio de Janeiro, Brazil, Sunday, August 7, 2016. (Photo by Hassan Ammar/AP Photo)

2016 Rio Olympics, Athletics, Women's Heptathlon Javelin Throw, Groups, Olympic Stadium, Rio de Janeiro, Brazil on August 13, 2016. Evelis Aguilar (COL) of Colombia competes in Javelin group A women's heptathlon. (Photo by Dylan Martinez/Reuters)