South Sudanese wrestlers take part in a wrestling match for peace in Juba on April 19, 2016. The last wrestling match for peace was held in Juba the day before civil war broke out in December 2013. (Photo by Carl de Souza/AFP Photo)

Iraqi army soldiers fire mortars against the Islamic State militants, at Shahrazad village 2 miles (3 kilometers) east of Mosul, Iraq, Monday, November 14, 2016. A suicide bombing in Iraq targeted the Shiite sacred city of Karbala on Monday, killing at least six civilians, the latest attempt by the Islamic State group to distract from the government forces' offensive on the IS-held northern city of Mosul. (Photo by Hussein Malla/AP Photo)

Members of the Indonesian Presidential Security Forces (Paspampres) show their skills during the simulation of a terrorist attack in Jakarta, Indonesia, 29 December 2016. According to reports in local media the Indonesian security forces have already arrested 21 terrorists suspects and fatally shot five of them, who were allegedly planning attacks in the Indonesian capital during the Christmas and New Year's Eve celebrations this year. The presentation was shown on the occasion of a visit by Indonesian President Joko Widodo and a delegation to the Paspampres headquarters in Jakarta. (Photo by Bagus Indahono/EPA)

7th August 1941: A Soviet sniper targets the enemy with the telescopic sight on his rifle.

Sixty-eight year old cross-country runner Rosie Swale-Pope is interviewed while sitting in her cart, “The Icebird”, in Upperville, Virginia March 13, 2015. Swale-Pope, who is from Great Britain and once ran an unsupported 20,000 mile run around the globe, is currently running across the United States from New York City to San Francisco in support of cancer research. (Photo by Gary Cameron/Reuters)

Dr. Anton Lim is interviewed by the media as he holds Kabang, a two-year-old injured mixed breed, upon arrival at the Ninoy Aquino International Airport in Pasay city, south of Manila, Philippines, early Saturday June 8, 2013 from San Francisco, Calif. Kabang lost her snout and upper jaw saving two girls' lives in the Philippines was headed back to its owner following treatment at the University of California, Davis veterinary hospital. (Photo by Bullit Marquez/AP Photo)

A prisoner from the Pedrinhas prison is carried to receive medical help after he was injured during a fight between rival gangs inside the jail, in Sao Luiz, capital of Maranhao state, January 8, 2014. The recent posting on a major Brazilian news website of a video filmed last December 17 by Pedrinhas prisoners of the decapitated and tortured bodies of rival inmates inside the jail has highlighted some of the problems present in the country's prison system which houses nearly twice as many prisoners as its capacity, according to official statistics. (Photo by Douglas Cunha/Reuters/O Estado do Maranhão)