A young man, who says he is part of a local criminal gang, poses for a picture holding a gun in the neighbourhood of Korogcho in Nairobi, Kenya, March 19, 2015. Around 2 million people live in the shantytowns packed in around Kenya's capital. Crime is high amid chronic unemployment levels, while basic services and sanitation are scarce. Residents try to make the best of things, eking out a living and picking up work where they can. (Photo by Siegfried Modola/Reuters)

A newly born Mexican gray wolf cub, an endangered native species, is seen at its enclosure at the Museo del Desierto in Saltillo, Mexico, July 19, 2016. Though once held in high regard in Pre-Columbian Mexico, it is the most endangered gray wolf in North America, having been extirpated in the wild during the mid-1900s through a combination of hunting, trapping, poisoning and digging pups from dens. (Photo by Daniel Becerril/Reuters)

A man carries food supplies on a donkey to Dhalamlam Mountain in the Jafariya district of the western province of Raymah, Yemen June 2, 2016. In villages perched high on a mountain in Western Yemen, residents are a safe distance from a conflict raging throughout most of the country but have had to turn the clock back on their lifestyles by centuries. (Photo by Abduljabbar Zeyad/Reuters)

In this handout image provided by NASA, the space shuttle Endeavour is seen on launch pad 39a as a storm passes by prior to the rollback of the Rotating Service Structure (RSS) April 28, 2011, at Kennedy Space Center in Cape Canaveral, Florida. During the 14-day mission, Endeavour and the STS-134 crew will deliver the Alpha Magnetic Spectrometer (AMS) and spare parts, including two S-band communications antennas, a high-pressure gas tank and additional spare parts for Dextre. Launch is targeted for April 29 at 3:47 p.m. EDT.

Israeli magician Hezi Dean stands atop of a tower where he intends to remain for 35 hours, at Rabin square on May 18, 2011 in Tel Aviv, Israel. Dean started his most recent stunt Wednesday in an attempt to break the record of American illusionist and endurance artist David Blaine. Dean was raised on the 27-meters high tower Wednesday morning and aims to remain there with no food until Thursday evening, for a total of 35-hours. (Photo by Uriel Sinai/Getty images)

A traveller washes his horse in the River Eden in preparation for selling at the Appleby Horse Fair on June 3, 2011 in Appleby, England. Appleby Horse Fair has existed under the protection of a charter granted by James II since 1685. It is one of the key gathering points for the Romany, gypsy and traveling community. Appleby Horse Fair is attended by about 5,000 travelers who come to buy and sell horses. The animals are washed and groomed before being ridden at high speed along the “mad mile” for the viewing of potential buyers. (Photo by Christopher Furlong/Getty Images)

NASA space shuttle Atlantis in Earth orbit is seen during a Rendezvous Pitch Maneuver, or back flip to enable space station crew members to take high resolution digital pictures of the shuttle's heat shield before docking for the last time with the International Space Station July 10, 2011 in space. Atlantis has embarked on a 12-day mission to the International Space Station where it will deliver the Raffaello multi-purpose logistics module packed with supplies and spare parts. This will be the final launch of the space shuttle program, which began on April 12, 1981 with the launch of Colombia. (Photo by NASA via Getty Images)

Israeli police officers confront demonstrators as Israelis protest against rising housing prices and social inequalities on July 30, 2011 in Tel Aviv, Israel. Tens of thousands of Israelis took to the streets in 10 cities across the country to protest against the high cost of living, including more than 50,000 in downtown Tel Aviv. The demonstrators rallied in support of hundreds of people who have set up protest camps against the government's economic and social policies. (Photo by Uriel Sinai/Getty Images)