Members of the Legio X Fretensis (Malta) re-enactment group take part in a display of ancient Roman army life at Fort Rinella in Kalkara, outside Valletta, March 22, 2015. The event “Romanus”, organised by the Malta Heritage Trust, consisted of talks, hands-on displays, static exhibitions of weapons and equipment, food and wine tasting and large-scale re-enactments depicting different forms of Roman warfare in the field. (Photo by Darrin Zammit Lupi/Reuters)

In this March 17, 2015 photo, Ashaninka Indian men, identified by locals as illegal loggers, tie tree trunks together to move them along the Putaya River near the hamlet of Saweto, Peru. Illegal logging persists unabated in this remote Amazon community where four indigenous leaders who resisted it were slain in September. The Putaya River is the waterway that transports felled trees, cut both legally and illegally, to the city of Pucallpa. (Photo by Martin Mejia/AP Photo)

A farmer harvests broccoli in the town of al-Ansariyeh south of Sidon, Lebanon March 15, 2016. (Photo by Ali Hashisho/Reuters)

An aircraft passes over houses at it lands at Heathrow Airport near London, Britain, December 11, 2015. Picture taken December 11, 2015. (Photo by Neil Hall/Reuters)

Police in riot gear hold back demonstrators against U.S. Republican presidential candidate Donald Trump outside the Hyatt hotel where Trump is set to speak at the California GOP convention in Burlingame, California, U.S., April 29, 2016. (Photo by Noah Berger/Reuters)

Freida Pinto as Jas Mitra in Showtime's “Guerrilla”, 2016. (Photo by Sky UK Limited/SHOWTIME)

South African Sangomas are wizards and witches who are supposedly chosen by their ancestors to follow a traditional training and go through a rite of passage after which they become Sangomas and can cure and help people. They are so respected and trusted that western medical authorities have actually advised the government of South Africa to develop its cooperation with Sangomas in order to improve hygiene and health among the population. (Photo by Patrick Durand/Sygma via Getty Images)

A U.S. Marine leads training on a shooting range in France in an undated photo taken during the First World War. (Photo by Reuters/Courtesy Library of Congress)