A woman dressed up as a zombie takes part in a zombie walk in the Gaslamp Quarter during the Comic Con International convention in San Diego, California July 13, 2012. (Photo by Mario Anzuoni/Reuters)

Sinabung mount spews ash to the air during an eruption near from Karo, North Sumatra on January 7, 2014. An Indonesian volcano that has erupted relentlessly for months shot volcanic ash into the air 30 times on January 4, forcing further evacuations with more than 20,000 people now displaced, an official said. (Photo by Sutanta Aditya/AFP Photo)

Rebels of the Revolutionary Armed Forces of Colombia (FARC) visit as they wait to have lunch in El Diamante, Colombia, Friday, September 16, 2016. FARC rebels are gathering for a congress were delegates will debate and vote on the accord reached last month with the Colombian government to end five decades of war. (Photo by Ricardo Mazalan/AP Photo)

Comandos de Salvamento rescuers Maria Martinez (L) and Ana Chichilla attend to a wounded homeless man in San Salvador, El Salvador July 16, 2016. The man was attacked with a machete by suspected gang members. In 2015, El Salvador registered a record 103 homicides per 100,000 habitants, making it one of the most dangerous countries in the world outside a war zone. But for many young people who have few chances to distance themselves from rivalries between so-called maras in their schools and neighbourhoods, a civil-society organisation called the Comandos de Salvamento, or Rescue Corps, has been a refuge. (Photo by Jose Cabezas/Reuters)

A leaflet denouncing South Korean President Park Geun-hye lies on the ground after it was torn at a protest calling Park to step down, in Seoul, South Korea, November 19, 2016. (Photo by Kim Hong-Ji/Reuters)

An abandoned motorboat is seen on the bank of a bay near Krabozavodskoye settlement on the Island of Shikotan, one of four islands known as the Southern Kuriles in Russia and the Northern Territories in Japan, December 19, 2016. (Photo by Yuri Maltsev/Reuters)

The waning moon is setting over the mountain “Les Cornettes de Bise” located at the border of the Haute-Savoie and the Valais canton of Switzerland in the Chablais Alps, photographed from Glutieres, January 7, 2015. (Photo by Anthony Anex/EPA)

Ukrainians wearing traditional costumes sing Kolyadky or Ukrainian Christmas Carols, as a part of Orthodox Christmas in Kiev, Ukraine, Thursday, January 7 2016. Orthodox Christians mark their traditional Christmas Day Jan. 7, with many ancient symbolic events. (Photo by Sergei Chuzavkov/AP Photo)