A duck salesman parades his stock to commuters at a busy station in Dhaka, Bangladesh on May 23, 2018. (Photo by Nazmul Hasan Khan/Caters News Agency)

A migrant carries his belongings as he arrives at the Beijing railway station to catch a train in Beijing, Friday, February 13, 2015. (Photo by Andy Wong/AP Photo)

A Russian army conscript called up for service in the Kremlin regiment and a woman say farewell at Yekaterinburg-Passazhirsky railway station in Yekaterinburg, Russia on November 15, 2018. (Photo by Donat Sorokin/TASS Russian News Agency)

A mob attacks a female police officer accused of shooting a protester in the Buterere neighborhood of Bujumbura, Burundi, May 12, 2015. Protesters opposed to the president's decision to run for a third term chased, beat and stoned the woman, who was later handed back to the police. (Photo by Goran Tomasevic/Reuters)

An anti-government protester sits on the ground in front of police during a demonstration in Sarajevo February 6, 2014. Hundreds of people turned out in solidarity in the capital Sarajevo, with teenagers throwing eggs and stones at a government building and fought with police. Four officers were taken to hospital, officials said. (Photo by Dado Ruvic/Reuters)

New York Police Department tactical police officers stand guard near the New York Stock Exchange on September 9, 2011 in New York City. Officials are stepping up security in New York and Washington D.C. a day after U.S. officials received a credible but unconfirmed terror threat to utilize car bombs on bridges or tunnels in New York or Washington. (Photo by Justin Sullivan/Getty Images)

A protester runs from a jet of water shot from a police water cannon in the courtyard of the University of Santiago, during clashes between students and police, in Santiago, Chile, Thursday, May 14, 2015. In the capital and other cities across the country, high school and university students marched, for the second time this year, to demand education reform. (Photo by Luis Hidalgo/AP Photo)

Metropolitan Transit Authority (MTA) Police Officer Keith Flood trains with his K-9 partner Doc, a German Shepherd, inside the “warehouse room” at the new MTA Police Department Canine Training Center in Stormville, New York, U.S., June 6, 2016. (Photo by Mike Segar/Reuters)