Farmers clash with riot policemen during a protest outside the Greek Agriculture Ministry on March 8, 2017 in Athens, Greece. Two people were detained after the windows of two police vans were smashed as approximately 1,000 farmers, mainly from the island of Crete, took part in the protest. (Photo by Nikolas Georgiou/ZUMA Wire/Rex Features/Shutterstock)

A woman cries after riot police dispersed demonstrators during protests to oust Narok county Governor Samuel Tunai in Narok, Kenya, January 26, 2015. At least seven people were injured on Monday in clashes between Kenyan police and protesters from the Maasai ethnic group who accuse a local governor of corrupt handling of tourism funds from the Maasai Mara game reserve, the Kenya Red Cross said. (Photo by Thomas Mukoya/Reuters)

A police officer jump ropes with a police dog at a police dog training base on July 11, 2011 in Beijing, China. The Police Dog Training Base was opened to a media visit to show the dogs skills to the public. (Photo by ChinaFotoPress/Getty Images)

Police clash with “Occupy Melbourne” protestors on October 21, 2011 in Melbourne, Australia. Protesters and riot police clashed in Melbourne today after police, acting on a Melbourne City Council eviction order, attempted to break up the crowd of hundreds that had been positioned in City Square for a week. (Photo by Mark Dadswell/Getty Images)

Haitians pull a car atop a pushcart in Port-au-Prince, October 11, 1994. The price of gasoline has fallen to about $6 US per gallon since U.S. forces occupied Haiti. Before, gasoline had cost as much as $10 U.S. per gallon. (Photo by Eric Draper/AP Photo)

A woman looks at La Paz city from the Jacha Qhatu cable car station in El Alto, July 23, 2015. Bolivia already has the largest urban cable car system in the world. Now the booming country is tripling the size of the network and will soon have nine lines whizzing above the administrative capital of La Paz. (Photo by David Mercado/Reuters)

Participants fancy dressed go downhil in the XXVII Car Festival in a homemade cart in the Santa Elena Municipality, near Medellin, Antioquia department, Colombia, on December 18, 2016. (Photo by Raul Arboleda/AFP Photo)

Michael Fröhlich's Jowett Javelin rotting car in his forest sculpture park in Neandertal Germany, September 11, 2016. An eccentric artist has collected fifty vintage cars and left them to rot in a forest – and now they're worth over $1 million. Former racing driver Michael Fröhlich, from Dusseldorf, Germany, has purposely crashed the cars into trees, buried them in mud and parked them on cliff faces in his estate's garden in the middle of the German Neanderthal. His collections includes a Jaguar XK120 worth $170,000, a Porsche 356 racer and a Buick worth $17,000. (Photo by Christoph Hagen/Barcroft Images)