An Israeli teenager crawls through mud as he participates in an annual combat fitness training competition, as part of his preparations ahead of his compulsory army service, near Kibbutz Yakum, central Israel February 19, 2016. (Photo by Baz Ratner/Reuters)

A woman and a girl dressed in historical Red Army uniform, wait before watching the Victory Day parade, marking the 71st anniversary of the victory over Nazi Germany in World War Two, at Red Square in Moscow, Russia, May 9, 2016. (Photo by Grigory Dukor/Reuters)

A Free Syrian Army (FSA) fighter reacts as he mourns near the body of his brother, who was an FSA fighter and died during an offensive against Islamic State fighters to take control of Qabasin town, on the outskirts of the northern Syrian town of al-Bab, Syria January 10, 2017. (Photo by Khalil Ashawi/Reuters)

Nicaraguan army members carry a participant playing the role of a victim during a national multi-hazard drill organized by the National System for Prevention, Mitigation and Attention to Disasters (SINAPRED), in the 30 de Mayo neighborhood in Managua, Nicaragua, September 26, 2016. (Photo by Oswaldo Rivas/Reuters)

Fatima Rezai, 21, a female officer from the Afghan National Army (ANA) practices with a punch bag during an exercise session at at the Kabul Military Training Centre (KMTC) in Kabul, Afghanistan October 23, 2016. (Photo by Mohammad Ismail/Reuters)

Soldiers of People's Liberation Army (PLA) Lanzhou Military Region jump through a burning obstacle during a training session at a military base in Tianshui, Gansu province, China, January 6, 2016. (Photo by Reuters/Stringer)

U.S. Army soldiers with the 1st Battalion, 501st Infantry Regiment deployed to Combat Outpost Sabari, Afghanistan scan their area as they begin a multi-day air assault mission near the Pakistani border of eastern Afghanistan's Khost province May 2, 2012. (Photo by Staff Sgt. Joshua L. DeMotts/U.S. Air Force)

Female Afghan National Police (ANP) officers aim their weapons during a drill at a training centre near the German Bundeswehr army camp Marmal in Mazar-e-Sharif, northern Afghanistan on December 11, 2012. (Photo by Fabrizio Bensch/Reuters/File Photo)