Migrants scramble aboard a train at the station in Beli Manastir, Croatia September 18, 2015. Migrant numbers in Europe will build up in coming days and their flows may fragment further into new routes, the U.N. refugee agency said on Friday, urging the European Union to grasp a last chance to resolve the refugee crisis next week. (Photo by Laszlo Balogh/Reuters)

An Indian soldier from the international peace keeping force (IPKF) instructs young Sri Lankan recruits in shooting, part of the training given to the citizen's volunteer force in the North-Eastern Sri Lankan city of Batticaloa, September 28, 1989. (Photo by Barbara Walton/AP Photo)

A passenger takes off his pants as others not wearing pants dance while waiting for a subway train during the “No Pants Subway Ride” in Mexico City, Mexico, February 21, 2016. The event is an annual flash mob and occurs in different cities around the world, according to its organisers. (Photo by Carlos Jasso/Reuters)

Jordanian soldiers pose after the opening ceremony of eighth annual Warrior Competition at the King Abdullah Special Operations Training Center (KASOTC) in Amman, Jordan, May 2, 2016. Twenty Seven Teams from Eleven countries are participating in a competition to test their military skills. (Photo by Muhammad Hamed/Reuters)

School teachers and staff members take part during an active shooter training at James I. O'Neill High School in Highland Falls, New York, U.S., December 12, 2017. (Photo by Eduardo Munoz/Reuters)

An elephant “kisses” a visitor during a show at an elephant training school in Xishuangbanna, Yunnan province, April 18, 2015. Some 16 elephants live at the school and give four 30-minute performances everyday for visitors. (Photo by Wong Campion/Reuters)

A police officer gives instructions to migrants rushing to board a train that would take them towards Serbia, at the railway station in the southern Macedonian town of Gevgelija, Wednesday, August 20, 2015. Macedonian police stepped up the security at the border with Greece apparently trying to stem recent surge of migrants who are coming from Greece. (Photo by Darko Vojinovic/AP Photo)

A woman from a group called “Las Patronas” (The bosses), a charitable organization that feeds Central American immigrants who travel atop a freight train known as “La Bestia”, passes food and water to immigrants on their way to the border with the United States, at Amatlan de los Reyes, in Veracruz state, Mexico October 22, 2016. (Photo by Daniel Becerril/Reuters)