Rebel fighters from the Jaish al- Fatah (or Army of Conquest) brigades manoeuver an alleged explosive- rigged make- shift armoured vehicle during a major assault on Syrian government forces West of Aleppo city on October 28, 2016 Syrian opposition fighters launched a major assault on government forces to break a months- long siege of rebel- held neighbourhoods of the battered city of Aleppo. Rebel groups including the powerful Ahrar al- Sham faction and former Al- Qaeda affiliate Fateh al- Sham Front fired waves of rockets into government- held western Aleppo, killing at least 15 civilians, a monitor said. (Photo by Omar Haj Kadour/AFP Photo)

Men are held by Iraqi national security agents, to be interrogated at a checkpoint, as oil fields burn in Qayara, south of Mosul, Iraq, Saturday, November 5, 2016. Islamic State fighters launch counterattacks in the thin strip of territory Iraqi special forces have recaptured in eastern Mosul, highlighting the challenges ahead as the battle moves into more densely populated neighborhoods where coalition air power must be used more selectively. (Photo by Felipe Dana/AP Photo)

Havilland Mosquito KA 114 performs a low pass during an airshow commemorating the completion of its rebuild on September 29, 2012 in Ardmore, New Zealand. The plane was restored by Warbird Restorations at Ardmore Aerodrome and is the only flying Mosquito in the world. (Photo by Simon Watts)

Chinese military medics take part in a parade commemorating the 70th anniversary of Japan's surrender during World War II held in front of Tiananmen Gate in Beijing, Thursday, September 3, 2015. (Photo by Ng Han Guan/AP Photo)

Chechen Interior Minister Ruslan Alkhanov greets participants of the military parade to mark the Victory Day in Grozny, Russia, May 9, 2015. Russia marks the 70th anniversary of the end of World War Two in Europe on Saturday with a military parade, showcasing new military hardware at a time when relations with the West have hit lows not seen since the Cold War. (Photo by Reuters/Host Photo Agency/RIA Novosti)

In this photo taken on Friday, July 14, 2017, a student at a paramilitary camp for children calls the rank to attention outside Kiev, Ukraine. As the deadly conflict in eastern Ukraine entered its third year, some parents in Ukraine are anxious to make sure their children are ready to fight it, instead of swimming and playing volleyball. (Photo by Efrem Lukatsky/AP Photo)

A reveller covered in tomato pulp takes part in the annual “Tomatina” festival in the eastern town of Bunol, on August 30, 2017. The iconic fiesta – which celebrates its 72nd anniversary and is billed at “the world's biggest food fight” – has become a major draw for foreigners, in particular from Britain, Japan and the United States. (Photo by Jaime Reina/AFP Photo)

South Vietnamese forces escort suspected Viet Cong officer Nguyen Van Lem (also known as Bay Lop) on a Saigon street February 1, 1968, early in the Tet Offensive. Moments later, Lem was executed by Gen. Nguyen Ngoc Loan, chief of the national police. (Photo by Eddie Adams/AP Photo)