Participants costumed as zombies try to catch hobby runners during the so-called Zombie-Run at the harness racing track Karlshorst in Berlin, Germany, 18 May 2014. The runners carry small flags in their belts which they have to get safely across the finishing line while the zombies try to steal them. The sporting event is based on the US television series “The Walking Dead”. (Photo by Soeren Stache/DPA)

South Korean football fans react during a public screening in Seoul of the South Korea vs Russia football match at the 2014 World Cup in Brazil, early on June 18, 2014. (Photo by Ed Jones/AFP Photo)

These two young siblings appear to cling on to a tree for dear life and even hold hands as they learn the ropes of climbing, on June 25, 2013. (Photo by Tim Fitzharris/Minden/Solent)

(L-R) Recording artists Ally Brooke, Normani Hamilton, Dinah-Jane Hansen, Lauren Jauregui and Camila Cabello of Fifth Harmony attend the 2016 Billboard Music Awards at T-Mobile Arena on May 22, 2016 in Las Vegas, Nevada. (Photo by David Becker/Getty Images)

Artists perform during the Closing Ceremony of the Rio 2016 Olympic Games at the Maracana Stadium in Rio de Janeiro, Brazil, 21 August 2016. (Photo by Sergei Ilnitsky/EPA)

In this January 31, 2014 file photo released by the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA), shows residents of the besieged Palestinian camp of Yarmouk, queuing to receive food supplies, in Damascus, Syria. That year, the U.N. was able to deliver food to about five percent of people in besieged areas including Yarmouk, while today estimates show the organization is reaching less than one percent. (Photo by UNRWA via AP Photo)

People participate in a pillow fight to mark International Pillow Fight Day in the Heroes' Square, in central Budapest, Hungary, Saturday, April 2, 2016. The Pillow Fight Day attracts tens of thousands people in more than 100 cities all over the World each year. ((Photo by Zoltan Balogh/MTI via AP Photo)

A woman takes a picture of a Maserati's SUV model Levante during the Auto China 2016 show in Beijing, China April 25, 2016. (Photo by Kim Kyung-Hoon/Reuters)