Fire fighters, emergency service vehicles and a helicopter in Moskovsky Prospekt at the entrance to Tekhnologichesky Institut station of the St Petersburg metro in the aftermath of an explosion which occurred in a train at 14:40 Moscow timeon April 3, 2017. (Photo by Peter Kovalev/TASS)

People spray water in the street ahead of “Songkran”, the annual Thai New Year water-throwing festival, in Kowloon City, Hong Kong, China, 09 April 2017. The pouring of water is a key element in the festival as it represents purification and the washing away of one's sins and bad luck for the year. The event also includes a “Miss Songkran” pageant where contestants are clothed in traditional Thai dress, and a winner is crowned. This year's “Songkran” will begin in Thailand on 13 April 2017. (Photo by Alex Hofford/EPA)

A skier in a costume attempts to cross a pool of water at the foot of a ski slope while competing in the annual “Gornoluzhnik” amateur event marking the end of the ski season, at the Bobrovy Log ski resort in the suburbs of the Siberian city of Krasnoyarsk, Russia, April 16, 2017. (Photo by Ilya Naymushin/Reuters)

A model falls over on the runway in a design by Victoria Bliss during the Project NextGen show at Mercedes-Benz Fashion Week Resort 18 Collections at Carriageworks on May 16, 2017 in Sydney, Australia. (Photo by Stefan Gosatti/Getty Images)

Cosplay fans (R) take selfies as comic book and gaming fans attend the annual Ani-Com and Games Fair in Hong Kong on July 28, 2017. Tens of thousands were expected to attend the annual event on animation, comics and games, from July 28 to August 1. (Photo by Isaac Lawrence/AFP Photo)

This August 28, 2017 photo shows eight-year-old Indian girl Bharti performing a balancing act on a rope during a street show in Batala, India. Travelling Indian performers, who earn a meagre income from putting on shows on the streets, often scout areas to gather a large street audience who then give money on a collection plate at the end of the show. (Photo by Narinder Nanu/AFP Photo)

A dog dressed as Oscar the Grouch takes part in the annual halloween dog parade at Manhattan's Tompkins Square Park in New York, NY, U.S. on October 21, 2017. (Photo by Lucas Jackson/Reuters)

Palestinians scuffle with Israeli forces at Damascus Gate in Jerusalem's Old City on December 8, 2017. Palestinians clashed with Israeli security forces after calls for a “day of rage” as US President Donald Trump's declaration of Jerusalem as Israel's capital sent shockwaves through the region for a second day. (Photo by Thomas Coex/AFP Photo)