An officer is on fire as demonstrators clash with police during a protest against plans for new austerity measures on June 28, 2011 in Athens, Greece. Greece's largest labor unions have called for a 48-hour strike, while the Socialist government is beginning to push through legislation for cost cutting reforms. (Photo by Milos Bicanski/Getty Images)

Riot police face off with demonstrators at the “Occupy Denver” camp on October 29, 2011 in Denver, Colorado. Following a march by protesters, police moved in on their encampment to tear down recently erected tents. They arrested numerous protesters, pepper-sprayed others and others reportedly fired rubber bullets at the crowd during the confrontation. (Photo by John Moore/Getty Images)

A competitor scrambles in the mud under barbed wire during the Tough Guy Challenge 2009 at South Perton Farm on February 1, 2009 in Wolverhampton, England. The biannual event to raise cash for charity challenges thousands of international competitors to run through a gruelling set of 21 obstacles including water, fire and tunnels after a lengthy run at the start. (Photo by Christopher Furlong/Getty Images)

Performers wearing 19th century French military uniforms fire their weapons as they attack Allied forces during a reenactment of the Battle of the Nations, in a field in the village of Markkleeberg near Leipzig October 20, 2013. The east German city of Leipzig commemorated the 200th anniversary of the largest battle of the Napoleonic Wars on Sunday by reenacting the Battle of the Nations, with 6,000 military-historic association enthusiasts from all over Europe. The decisive encounter in which tens of thousands of soldiers were killed, took place from October 17-19, 1813, just outside of Leipzig. At the height of the hostilities Napoleon fielded more than 200,000 men against an Allied force of some 360,000 soldiers which included troops from Russia, Austria, Prussia and Sweden. (Photo by Fabrizio Bensch/Reuters)

In this photo taken Tuesday, February 2, 2016, asylum seekers gather round a fire as they cook a meal overlooking the temporary Altnes camp refugee camp on the island of Seiland, northern Norway. Waiting for their asylum claims to be processed, hundreds of people in emergency shelters in Hammerfest and neighboring towns are slowly getting used to the extreme climate and unfamiliar customs of the High North. They say they have adapted to the cold – the temperature rarely drops below minus 10 degrees C (14 F) along the coast, though it gets much colder further inland. It’s the darkness that throws them off. (Photo by Alastair Grant/AP Photo)

“Tough Times for Orangutans”. Nature, first prize stories. Tim Laman, USA. Location: West Kalimantan, Indonesia. A Bornean orangutan climbs over 30 meters up a tree in the rain forest of Gunung Palung National Park, West Kalimantan, Indonesia, August 12, 2015. The lives of wild orangutans are brought to light. Threats to these orangutans from fires, the illegal animal trade and loss of habitat due to deforestation have resulted in many orphan orangutans ending up at rehabilitation centers. (Photo by Tim Laman/World Press Photo Contest)

A child coughs as migrants and refugees run away after Macedonian police fired tear gas at hundreds of Iraqi and Syrian migrants who tried to break through the Greek border fence in Idomeni, on February 29, 2016. Greek police said more than 6,000 people were massed at the border, in a buildup triggered by Austria and Balkan states capping the numbers of migrants entering their territory. (Photo by Louisa Gouliamaki/AFP Photo)