A tank's barrel is seen on the course of the Tank Biathlon competition during the International Army Games 2016 in Alabino, outside Moscow, Russia, July 30, 2016. (Photo by Maxim Zmeyev/Reuters)

Salvadoran indigenous participate in the International Day of the Indigenous Peoples at Divino Slavador square in San Salvador, El Salvador, 09 August 2016. (Photo by Oscar Rivera/EPA)

A man pedals his cycle rickshaw during monsoon rains in New Delhi, India August 31, 2016. Normal life was thrown out of gear as heavy rainfall lashed the city Wednesday morning, resulting in waterlogging and traffic jams. (Photo by Cathal McNaughton/Reuters)

A Palestinian man reacts after his house was flooded by rain water in Khan Younis in the southern Gaza Strip, November 9, 2015. (Photo by Ibraheem Abu Mustafa/Reuters)

An Aymara woman with a sheep waves to the crowd during a Christmas parade in La Paz, Bolivia December 12, 2015. (Photo by David Mercado/Reuters)

A man helps a child to dress as Jawa, a character from the Star Wars movie series, during an event organised by Star Wars fan club Monterrey in Monterrey, Mexico, December 13, 2015. (Photo by Daniel Becerril/Reuters)

Children wearing uniforms hold toy guns during a military parade game on China's National Day, at Beyou World, a centre children where can experience different kinds of professions, in Beijing, October 1, 2015. (Photo by Reuters/Stringer)

An employee of the National Park Service takes a selfie with President Barack Obama, left, in the background meeting with the crowd after a tour of Everglades National Park on Earth Day, Wednesday, April 22, 2015, in Florida. Obama used the visit to warn of the damage that climate change is already inflicting on the nation's environmental treasures. (Photo by Lynne Sladky/AP Photo)