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)

Young revelers take part in a parade called "La Calabiuza" on November 1, 2015, on the eve of the Day of the Dead in Tonacatepeque, 20 kms (13 miles) north of San Salvador. During the celebration, the residents of Tonacatepeque, originally an indigenous community, recall the characters from the mythology of Cuscatlan – pre-Columbian west and central regions of El Salvador – and their dead relatives. (Photo by Marvin Recinos/AFP Photo)

Tourists ice skate at night on the Eiffel Tower's skating rink in Paris December 9, 2014. The skating rink, located on the first level of the Eiffel Tower, opens to the public as part of the Christmas holiday season. (Photo by Charles Platiau/Reuters)

Belarussian rhythmic gymnast Melitina Staniouta takes a selfie as she has her make-up done in Minsk, May 29, 2016. Photos show her training and competing, as well as trying on her official Olympic uniform and getting ready for a photo shoot. (Photo by Vasily Fedosenko/Reuters)

A woman holds a champagne bottle during New Year's celebrations in Bucharest, Romania, Wednesday, January 1, 2014. Tens of thousands of Romanians took to the streets of the Romanian capital to join parties and watch fireworks. (Photo by Vadim Ghirda/AP Photo)

A man impersonating Kim Jong-un gestures during the athletics at the Rio 2016 Olympic Games at the Olympic Stadium in Rio de Janeiro on August 18, 2016. (Photo by Johannes Eisele/AFP Photo)

An Israeli boy looks through the sight of a weapon during a display of Israeli Defense Forces (IDF) equipment and abilities at the West Bank settlement of Kiryat Arba, April 23, 2015, during celebrations for Israel's Independence Day, marking the 67th anniversary of the creation of the state. (Photo by Ronen Zvulun/Reuters)

Sergey, one of the participants of PARTISAN courses, poses for a portrait in an abandoned building in Olgino, St. Petersburg, Russia on November 23, 2016. Sergey came to St. Petersburg from the city of Cheliabinsk to attend an intensive seven-day program. Sergey is a businessman, a traveller and a blogger. His another passion are “men's hobbies”, that's why he participated in the paramilitary courses. (Photo by Alexander Aksakov/The Washington Post)