A news crew runs from flames southeast of Middletown, Calif., on Tuesday, September 15, 2015, as winds kick up the Valley fire. (Photo by Wally Skalij/Los Angeles Times/TNS)

Children guarded by Hungarian police play on the ground after being detained along with other migrants who illegally crossed from Serbia to Hungary near the village of Asotthalom, Hungary, September 16, 2015. (Photo by Dado Ruvic/Reuters)

A walker has left a handprint on a snow- covered tree trunk on Grosser Feldberg mountain in the Taunus mountain range, Germany, 16 January 2017. (Photo by Frank Rumpenhorst/DPA)

A member of Libyan forces allied with the U.N.-backed government fires a weapon on a pickup truck during a battle with Islamic State militants in Giza Bahreya, in Sirte, Libya October 27, 2016. (Photo by Hani Amara/Reuters)

A weapon is being destroyed during an exercise to disable seized weapons in Caracas, Venezuela August 17, 2016. (Photo by Marco Bello/Reuters)

A historical re-enactor poses for a photograph in a living history camp as he prepares to take part in an anniversary event for the Battle of Bosworth near Market Bosworth in central Britain August 22, 2015. The Battle of Bosworth took place in 1485 during the War of the Roses between the Houses of Lancaster and the House of York. King Richard III was defeated by Henry Tudor marking the end of Plantagenet rule and the beginning of the Tudor dynasty. (Photo by Neil Hall/Reuters)

A girl carries a bag of recyclable items she collected from a landfill on the outskirts of Sanaa, Yemen November 16, 2016. (Photo by Mohamed al-Sayaghi/Reuters)

An employee operates a machine while attaching a lock to a silver chain at the jewelry department of the Krastsvetmet non-ferrous metals plant, one of the world's largest producers in the precious metals industry, in the Siberian city of Krasnoyarsk, Russia, December 14, 2016. (Photo by Ilya Naymushin/Reuters)