A boy stands in the ruins of a house destroyed by a Saudi-led air strike in Yemen's capital Sanaa, September 13, 2015. (Photo by Mohamed al-Sayaghi/Reuters)





Gustavo and Otavio Pandolfo, painters representing “Osgemeos” (the twins) from Brazil, paint a wall during the street-art festival “Vulica Brazil” ahead of celebrations for the Day of Minsk, in Minsk, Belarus, September 7, 2015. (Photo by Vasily Fedosenko/Reuters)





A man walks past a mural in East Belfast in Northern Ireland, September 18, 2015. (Photo by Cathal McNaughton/Reuters)





A man walks past a mural in East Belfast in Northern Ireland, September 18, 2015. (Photo by Cathal McNaughton/Reuters)





A woman walks past graffiti in the Bogside area of Londonderry in Northern Ireland, September 25, 2015. (Photo by Cathal McNaughton/Reuters)





A boy walks past Republican graffiti in the Bogside area of Londonderry in Northern Ireland, September 25, 2015. (Photo by Cathal McNaughton/Reuters)





A man rides his bike past a graffiti depicting Europe as a Grim Reaper with a small door on his body, standing in front of a barbed wire fence and waving, in the northern city of Thessaloniki, Greece, September 29, 2015. A record number of at least 430,000 refugees and migrants have taken rickety boats across the Mediterranean to Europe this year, 309,000 via Greece, according to International Organization for Migration figures. (Photo by Alexandros Avramidis/Reuters)





People run past a mural on Skid Row in downtown Los Angeles, California, United States, October 1, 2015. Los Angeles officials last week moved to declare the rising problem of homelessness an "emergency" in the city and proposed spending $100 million to provide permanent housing and shelters to help the city's 26,000 indigent. (Photo by Lucy Nicholson/Reuters)





Cyclists ride their bicycles past a section of the Israeli barrier during a cycling challenge in the occupied West Bank city of Bethlehem October 2, 2015. (Photo by Mussa Qawasma/Reuters)





In this Thursday, August 20, 2015, photo, an Afghan boy walks in front of street art on a barrier wall of the NDS (National Directorate of Security) in Kabul, Afghanistan. (Photo by Rahmat Gul/AP Photo)





An Afghan passes by a mural on a barrier wall of the presidential palace in Kabul, Afghanistan, 18 August 2015. Mokamel and a group of artists wants to bring color into the grey streets of Kabul. (Photo by Hedayatullah Amid/EPA)





A Swedish street artist known as “Amara Por Dios” takes part in the “Sand Sea & Spray” Urban Art Festival in Blackpool, north west England on July 11, 2015. The festival, which concludes tomorrow, features live street art being produced on walls and billboards in various locations throughout central Blackpool. (Photo by Oli Scarff/AFP Photo)





Norwegian street artist “Zina” creates an artwork as she takes part in the “Sand Sea & Spray” Urban Art Festival in Blackpool, north west England on July 11, 2015. (Photo by Oli Scarff/AFP Photo)





A street artist creates an artwork as he takes part in the “Sand Sea & Spray” Urban Art Festival in Blackpool, north west England on July 11, 2015. (Photo by Oli Scarff/AFP Photo)





Street artists create artworks as they take part in the “Sand Sea & Spray” Urban Art Festival in Blackpool, north west England on July 11, 2015. (Photo by Oli Scarff/AFP Photo)





A workman walks past a large mural on the side of a building during the “Sand Sea & Spray” Urban Art Festival in Blackpool, north west England on July 11, 2015. (Photo by Oli Scarff/AFP Photo)





Street artists create artworks as they take part in the “Sand Sea & Spray” Urban Art Festival in Blackpool, north west England on July 11, 2015. (Photo by Oli Scarff/AFP Photo)





Women walk past a piece of street art created as part of the “Sand Sea & Spray” Urban Art Festival in Blackpool, north west England on July 11, 2015. (Photo by Oli Scarff/AFP Photo)





Street artist Will Bentham, known as “Lowdown”, creates an artwork as he takes part in the “Sand Sea & Spray” Urban Art Festival in Blackpool, north west England on July 11, 2015. (Photo by Oli Scarff/AFP Photo)





Street artists create artworks, as they take part in the “Sand Sea & Spray” Urban Art Festival in Blackpool, north west England on July 11, 2015. (Photo by Oli Scarff/AFP Photo)





French street artist “Akse” creates an artwork as he takes part in the “Sand Sea & Spray” Urban Art Festival in Blackpool, north west England on July 11, 2015. (Photo by Oli Scarff/AFP Photo)





A man passes graffiti in Athens, Tuesday, July 21, 2015. (Photo by Thanassis Stavrakis/AP Photo)





In this Monday, August 31, 2015 photo, soldiers guard a corner in a gang-controlled neighborhood in Ilopango, El Salvador. (Photo by Salvador Melendez/AP Photo)





An Iranian woman walks next to an anti-US moral on her way to former US embassy, in Tehran, Iran, September 2, 2015. (Photo by Abedin Taherkenareh/EPA)





An Iranian woman walks past a painting of a revolver, painted in an American-flag style, on the wall of former US embassy in Tehran, Iran, 02 September 2015. (Photo by Abedin Taherkenareh/EPA)





Graffiti artist Eduard Kasper works on his contribution to a joint graffiti project beneath the Theodor Heuss Bridge in Wiesbaden Mainz-Kastel, Germany, 15 June 2015. The bridge is sprayed anew by graffiti artists every year. (Photo by Fredrik von Erichsen/EPA)





John Nation, a guide from Bristol Street Art Tours shows a piece of street art as part of the ongoing Upfest 2015 festival being held in Bedminster on July 27, 2015 in Bristol, England. (Photo by Matt Cardy/Getty Images)





A Lebanese man on his scooter wears a face mask as he drives past a graffitti painted on a wall during a sandstorm blows over the Lebanese capital Beirut on September 8, 2015. The graffiti reads in Arabic “The new Lebanon is found” in reference to the “You Stink” non-partisan group which has organised a series of growing protests in recent weeks against Lebanon's political class and corruption. (Photo by Joseph Eid/AFP Photo)





A view of graffiti on a wall in Kabul, Afghanistan March 5, 2012. Encased in a head-to-toe burqa, the image depicts a distraught woman slumped on a cement stairwell, the work of Afghanistan's first street artists who use graffiti to chronicle violence and oppression. (Photo by Mohammad Ismail/Reuters)





Artist and activist Murad Subai puts final touches on his graffiti depicting Saudi, U.S. and Iranian currency banknotes on a wall, during a graffiti campaign against foreign interference in the internal affairs of Yemen, in Sanaa May 15, 2014. (Photo by Khaled Abdullah/Reuters)





A member of the Iraqi security forces stands guard with his weapon at Camp Habbaniyah between the cities of Fallujah and Ramadi, March 12, 2015. (Photo by Alaa Al-Marjani/Reuters)





A man sits next to a wall with Christian graffiti in a cell of the central prison in the district of Wango, in Bangui, Central African Republic March 21, 2014. (Photo by Siegfried Modola/Reuters)





A Free Syrian Army fighter poses next to graffiti on a wall drawn by Syrian artist and activist Ahmad Jalal along a street in Kafranbel, Idlib province, Syria January 31, 2014. Jalal's drawings have been used as banners during anti-government protests as well. (Photo by Fadi Mashan/Reuters)





People pose for a picture next to graffiti reading “Putler kaput” in Lviv, Ukraine May 9, 2014. (Photo by Reuters/Stringer)





A man walks past a graffiti, denouncing strikes by U.S. drones in Yemen, painted on a wall in Sanaa November 13, 2014. (Photo by Khaled Abdullah/Reuters)





Graffiti left behind by Taliban fighters remains on the walls of a compound now used as a command center for the U.S Marine Corps's First Battalion, Eighth Marines at Musa Qala in Helmand province, Afghanistan November 10, 2010. (Photo by Finbarr O'Reilly/Reuters)





A fuel pump is defaced with a graffiti caricature of Muammar Gaddafi in the rebel-held town of Ajdabiyah, Libya March 31, 2011. (Photo by Finbarr O'Reilly/Reuters)





A rebel fighter points his weapon at graffiti of Muammar Gaddafi on a checkpoint building controlled by rebels in Zintan July 15, 2011. (Photo by Ammar Awad/Reuters)





An artist paints graffiti on the wall of an industrial park in Kabul, Afghanistan December 19, 2010. The bus with no wheels and crammed with passengers is a stark comment on war-torn Kabul's appalling public transport. (Photo by Omar Sobhani/Reuters)





Graffiti reading “The Few, The Proud”, made by a previous deployment of the U.S Marine Corps, adorns the walls at Musa Qala in Helmand province, Afghanistan November 10, 2010. (Photo by Finbarr O'Reilly/Reuters)





British street artist Dale Grimshaw (2nd R) creates an artwork for the “Sand Sea & Spray” Urban Art Festival in Blackpool, north west England on July 11, 2015. (Photo by Oli Scarff/AFP Photo)