Riot police stand guard behind a fire as refinery workers hold a blockade of the oil depot of Douchy-Les-Mines to protest against the government's proposed labour reforms, on May 25, 2016. Refinery workers stepped up strikes that threaten to paralyse France weeks ahead of the Euro 2016 tournament as the government moved to break their blockades, escalating a three-month tug-of-war over labour reforms. (Photo by François L.O./AFP Photo)

A couple embrace during the start of the San Fermin festival in Pamplona, Spain July 6, 2016. Revelers from around the world kick off the festival with a messy party in the Pamplona town square, one day before the first of eight days of the running of the bulls. (Photo by Vincent West/Reuters)

A youth stands near a cow and a sheep that were sacrified in the village of Miratovc for the celebration of Eid-al-Adha, near the town of Presevo, southern Serbia September 24, 2015. Muslims across the world celebrate the annual festival of Eid al-Adha or the Feast of the Sacrifice. (Photo by Hazir Reka/Reuters)

A toddler sits on the winner of the giant pumpkin category during the RHS (Royal Horticultural Society) London Harvest Festival Show at RHS Lindley Halls on October 6, 2015 in London, England. The traditional harvest themed show runs October 6-7 and showcases a wide range of late summer grown fruit and vegetables. (Photo by Ben Pruchnie/Getty Images)

A man carrying a sailfish walks through Hamarweyne district in South Mogadishu on March 25, 2015. (Photo by Carl De Souza/AFP Photo)

David Jackson (C), who voted for Donald Trump, has a discussion with Ryan Graves (L) and Anna Kaminski (R) visiting from Oamaha, Nebraska during a rally against the election of Republican Donald Trump as President of the United States in downtown Indianapolis, Indiana, U.S., November 12, 2016. (Photo by Clay Lomneth/Reuters)

A wounded protester is attended before being rushed to a vehicle following violence in Independence Square in Kiev February 20, 2014. Ukrainian protesters seized back Kiev's Independence Square in fresh clashes with riot police on Thursday that left several injured and possibly two demonstrators dead. (Photo by Konstantin Chernichkin/Reuters)

Hot air balloons fly over the sky in Chiang Mai province, northern Thailand, December 6, 2014. The two-day International Balloon festival 2014 featuring balloon pilots from Germany, Spain, Netherlands, Britain, and Czech Republic is held on December 06-07 2014 to celebrate Thai King Bhumibol Adulyadej's 87th birthday and also aimed to promote the tourism industry in Chiang Mai northern city. (Photo by Pongmanat Tasiri/EPA)