Soldiers use electronic sensors to search for missing firefighters under a line of fire trucks caught in massive gas explosions in Kaohsiung, Taiwan, Friday, August 1, 2014. A series of underground explosions about midnight Thursday and early Friday ripped through Taiwan's second-largest city, killing scores of people, Taiwan's National Fire Agency said Friday. (Photo by Wally Santana/AP Photo)

In this Tuesday, June 23, 2015, photo, an Israeli vendor waits for clients at the southern Israeli town of Sderot, next to the Israel-Gaza border. A year after the Gaza war, the community in southern Israel, long battered by rockets from the Hamas-run territory next door, has slowly recovered and is even seeing a quiet boom. (Photo by Oded Balilty/AP Photo)

Farmer Franz Schaller rides on an ox called Napoleon during a traditional ox race in the southern Bavarian village of Muensing near Lake Starnberg, Germany August 28, 2016. (Photo by Michaela Rehle/Reuters)

A Los Angeles County firefighter puts water a burning house in a wildfire in the Lake View Terrace area of Los Angeles Tuesday, December 5, 2017. Ferocious winds in Southern California have whipped up explosive wildfires, burning a psychiatric hospital and scores of other structures. Tens of thousands of people have been ordered evacuated. (Photo by Chris Carlson/AP Photo)

Fire photographer Tod Sudmeier gets hit with flying embers from strong winds at the Solimar brush fire that started early Saturday morning in Ventura County, California December 26, 2015. (Photo by Gene Blevins/Reuters)

Jose, a reveller covered in grease, poses for a photo as he takes part in the annual Cascamorras festival in Baza, southern Spain September 6, 2015. The festival was inspired by a dispute between the town of Baza and Guadix over the possession of an icon of the Virgin of Piedad. The Cascamorras refers to representatives from Guadix, who were sent to Baza to recover the statue. As the Cascamorras had to stay perfectly clean to gain possession of the statue, Baza residents attempt to make them as “dirty” as possible. (Photo by Marcelo del Pozo/Reuters)

A passenger plane, with a full Harvest moon seen behind, makes its final landing approach towards Heathrow Airport in London, Britain, October 5, 2017. (Photo by Toby Melville/Reuters)

An Amur tiger walks across a passageway after a news conference at the Philadelphia Zoo, Wednesday, May 7, 2014, in Philadelphia. The see-through mesh pathway called Big Cat Crossing is part of a national trend called animal rotation that zoos use to enrich the experience of both creatures and guests. (Photo by Matt Slocum/AP Photo)