Iraqi troops fire artillery towards Islamic State (IS) group jihadists' positions in west Mosul on March 11, 2017 during the ongoing battle to retake the city from the group. (Photo by Aris Messinis/AFP Photo)

West Berliners crowd in front of the Berlin Wall as they watch East German border guards demolish a section of the wall on November 11, 1989. (Photo by Gerard Malie/AFP Photo)

“What did I know about Chechnya before last week? For someone who grew up in the 1990s the very word Chechnya meant a string of grainy images on TV showing people in battered camouflage outfits, shooting at each other amid destruction and ruin. Fear, wahhabis, Shamil Basayev, terrorism, mountains: these were the words that used to spring to my mind when someone mentioned Chechnya”. – Maxim Shemetov. Photo: Special forces officers stand guard during a government-organised event marking Chechen language day in the centre of the Chechen capital Grozny April 25, 2013. (Photo by Maxim Shemetov/Reuters)

The finishing touches are made to a giant sculpture on the Hayward Gallery entitled “Urban Fox” and made from straw bales on April 18, 2011 in London, England. The sculpture features in the Southbank Centre's 60th anniversary celebration of the 1951 Festival of Britain. The celebration will feature various cultural and creative events and runs from April 22 until September 4, 2011 at London's Southbank Centre. (Photo by Oli Scarff/Getty Images)

Ethnic Miao men wearing traditional masks smear dust on a woman's face to wish her good luck during local celebration event for Lunar New Year in Liuzhou, Guangxi Zhuang Autonomous Region, China, February 16, 2016. (Photo by Reuters/Stringer)

Vladimir Putin looks at a model of the Tupolev TU-160 bomber, or Blackjack, that was presented to him on his arrival in Olenegorsk, Russia, August 16, 2005. Putin flew in the Tupolev TU-160 bomber and took part in the launch of cruise missiles in the Arctic north. (Photo by Reuters/ITAR-TASS/Presidential Press Service)

People fall down as they try to form a human pyramid to break the “Dahi handi”, an earthen pot filled with curd, an integral part of celebrations to mark Janmashtami in Mumbai, India, Monday, August 18, 2014. Hindu devotees take part in the celebration in which an earthen pot is suspended high above the ground and groups of young men and children form a human pyramid to reach the pot and break it. The festival celebrates the birth of Hindu god Lord Krishna, one of the most popular gods in Hinduism. (Photo by Rafiq Maqbool/AP Photo)

Amanda Ashe of Oakland, left, faces off with a police officer during the second night of demonstrations in Emeryville, California, following the grand jury decision in the shooting of Michael Brown in Ferguson, Missouri, November 25, 2014. (Photo by Elijah Nouvelage/Reuters)