A demonstrator throw a firebomb during clashes with Turkish riot police officers in Istanbul, Turkey, Friday, May 1, 2015. The government assigned 30,000 police officers backed by helicopters as workers and demonstrators determined to defy a government ban, tried to march to iconic Taksim Square, where 35 people were killed during May Day celebration in 1977. (Photo by Emrah Gurel/AP Photo)

A traffic police woman whistles at a pedestrian, Monday, July 27, 2015, in Pyongyang, North Korea where its citizens are having a one-day national holiday to celebrate the country's 62nd anniversary of the armistice that ended the Korean War. (Photo by Wong Maye-E/AP Photo)

Sculptures entitled “The Rising Tide” by British sculptor Jason deCaires Taylor are seen beside the River Thames in front of the Houses of Parliament and the London Eye ferris wheel in London, September 3, 2015. The representations of four horses and riders are fully visible at low tide but become immersed underwater twice a day as the Thames rises to reach full tide. The installation will be on display throughout September as part of the annual Totally Thames festival. (Photo by Toby Melville/Reuters)

Dancers Daisy Kerry (R) and Alice Rathbone pose as characters from The Nutcracker, for the annual Christmas event at Chatsworth House near Bakewell in Britain November 4, 2016. (Photo by Darren Staples/Reuters)

Romanian military doctors and medical students sit on a bus behind steamy windows before the National Day parade in Bucharest, Romania, Thursday, December 1, 2016. Military planes and helicopters flew over the Romanian capital Thursday as thousands turned out to celebrate the national day, marking the date when the country reunified with Transylvania in 1918. (Photo by Vadim Ghirda/AP Photo)

A man dressed as Father Frost, Russian equivalent of Santa Claus, sits by the fire with a reindeer Yakut, marking winter solstice at the Royev Ruchey Park of Flora and Fauna in the Siberian Taiga wood in the suburbs of Krasnoyarsk, Russia, December 21, 2016. (Photo by Ilya Naymushin/Reuters)

A girl swims in floodwaters in Malaysia' s northeastern town of Rantau Panjang, which borders Thailand, on January 5, 2017 Floods in two northeast Malaysian states have now forced almost 23,000 people from their homes and extra relief centres have been opened, rescue officials said on January 4. (Photo by Mohd Rasfan/AFP Photo)

South African surfer Andy Marr rides a wave at Dungeons offshore reef in the Atlantic Ocean outside Cape Town, South Africa, 01 September 2016. The big wave surfing season is at its peak with winter swells driven by storms in the South Atlantic breaking on the Cape's outer reefs providing good conditions. Big wave surfers are competing in the 2016 Striped Horse Challenge and Rebel Sessions big wave competitons symultaneously throughout the season. (Photo by Nic Bothma/EPA)