Displaced Sunni people, who fled the violence in the city of Ramadi, arrive at the outskirts of Baghdad, April 17, 2015. Iraqi security forces fought Islamic State militants at the gates of the western city of Ramadi on Friday, and local authorities warned it was in danger of falling unless reinforcements arrived soon. (Photo by Reuters/Stringer)

A statue of The Earl of Beaconsfield looks on as a giant mechanical spider sits on the side of the derelict Concourse tower in Liverpool city centre on September 3, 2008 in Liverpool, England. The 50ft tall spider was commissioned for the city's European Capital of Culture year and will begin moving to explore the city operated by artists from French theatre company La Machine. (Photo by Christopher Furlong/Getty Images)

Police walk past a burning car during riots in Birmingham City Centre on August 8, 2011 in Birmingham, England. After three nights of rioting and looting in and around London, the chaos is starting to spread to other cities around Britain. (Photo by Jeff J Mitchell/Getty Images)

A clown performs next to the Monument to the Revolution as he takes part in the Latin American Clown Convention in Mexico City, Mexico, October 21, 2015. The convention will be held from October 19 to 22 in Mexico City. (Photo by Henry Romero/Reuters)

A boat is stranded on Poyang Lake in Lushan City, China during low-water season on November 3, 2016. (Photo by Xinhua/Barcroft Images)

Children play in front of a brick factory on the outskirts of the northern Myanmar city of Mandalay on December 14, 2015. (Photo by Phyo Hein Kyaw/AFP Photo)

New York City, 1974. (Photo by Elliott Erwitt/Harry Ransom Center Collection/Magnum Photos)

Labourers unload gravel from a boat docked in Dala township, opposite Yangon city, Myanmar, November 12, 2015. (Photo by Olivia Harris/Reuters)