A woman smokes a cigarette next to man wearing a mask during lunch hour at the central business district in Singapore September 29, 2015. The 3-hour haze Pollutant Standards Index (PSI) reached a high of 173 at 8am on Tuesday, according to the National Environment Agency. Slash-and-burn agriculture in neighboring Indonesia has blanketed Singapore in a choking haze for weeks. (Photo by Edgar Su/Reuters)

An attendee dances at the start of the “Big Goth Dance Party” during the Porcupine Freedom Festival, or PorcFest, the Free State Project's annual summer gathering in Lancaster, NH on Wednesday, June 25, 2014. (Photo by Matthew Cavanaugh/The Washington Post)

A riot policeman punches Greek photojournalist Tatiana Bolari during a demonstration in Athens' Syntagma (Constitution) square October 5, 2011. Police officers attacked several members of the press covering protests, injuring at least two members of the media. (Photo by Yannis Behrakis/Reuters)

“Honorable Mention”. An Indian rhinoceros, far from home and stuck inside with late-winter blues at the Toronto zoo. Photo location: Toronto, Ontario, Canada. (Photo and caption by Stephen De Lisle/National Geographic Photo Contest)

Residents of the Korean port of Inchon surrender to American troops. (Photo by Bert Hardy/Getty Images). 1950

North Kenya, Liboi. A young Somali refugee crosses a field filled with marabous storks in July 1992. (Photo by Jean-Claude Coutausse)

A combination picture shows Aleppo's Umayyad mosque, Syria, before it was damaged on March 12, 2009 (top) and after it was damaged (bottom) December 13, 2016. (Photo by Omar Sanadiki/Reuters)