Afghanistan's interior ministry special forces demonstrate their skills during a military exercise in Kabul, Afghanistan, Thursday, April 2, 2015. Afghanistan's security forces took over full responsibility for the country's security on January 1, 2015. (Photo by Massoud Hossaini/AP Photo)

A participant of the Wild Sau Dirt Run 2015 passes a mud barrier in Obertriesting, Lower Austria, Austria, Saturday, April 4, 2015. The Wild Sau Dirt Run is a cross country and steeplechase race for men and women over the distances of 5, 10 and 20 kilometers (3.1, 6.2 and 12.4 miles). (Photo by Ronald Zak/AP Photo)

Baby clouded leopards, born early in March 2015, are presented by zoo keepers at the Olmense Zoo in Olmen, Belgium, April 16, 2015. The clouded leopard is an endangered species with only some 10,000 specimen remaining on earth, said Robby Van der Velden, a biologist at the Olmense Zoo. (Photo by Yves Herman/Reuters)

A rescue helicopter is shown at the Mount Everest south base camp in Nepal a day after a huge earthquake-caused avalanche killed at least 17 people, in this photo courtesy of 6summitschallenge.com taken on April 26, 2015 and released on April 27, 2015. Rescue teams, helped by clear weather, used helicopters to airlift scores of people stranded at higher altitudes, two at a time. (Photo by Reuters/6summitschallenge.com)

A portrait of Kazakh historical figure Ablai Khan is projected on a building in downtown Astana, Kazakhstan, October 8, 2015. (Photo by Shamil Zhumatov/Reuters)

Students play in their school yard on the first day of the new school term at a primary school in Baghdad, October 18, 2015. (Photo by Ahmed Saad/Reuters)

Revellers take part in a zombie parade to celebrate Halloween in Vina del Mar, October 31, 2015. (Photo by Rodrigo Garrido/Reuters)

An Egyptian passenger sits on the locomotive of a train as it leaves Cairo train station in Egypt, Wednesday, October 14, 2015. (Photo by Amr Nabil/AP Photo)