Participants climb over a wall at the “Tough Mudder” endurance event series in Arnsberg September 6, 2014. Competitors who took part in the endurance event saw themselves having to overcome various military style obstacles. (Photo by Ina Fassbender/Reuters)

Sgt. William Olas Bee, a U.S. Marine from the 24th Marine Expeditionary Unit, has a close call after Taliban fighters opened fire near Garmsir in Helmand Province of Afghanistan, May 18, 2008. (Photo by Goran Tomasevic/Reuters)

Nightmare: New York”, staged in a Lower East Side building, depicts the ugliest, scariest vision of 1970s- and '80s-era Gotham. Subways are awash in graffiti, creeps and crime. Here: In this October 2, 2014 photo, an actor performs during “Nightmare: New York”, a haunted house attraction in New York. (Photo by Frank Franklin II/AP Photo)

Spectators cheer as the United Launch Alliance Delta 4-Heavy rocket, with NASA's Orion spacecraft mounted atop, lifts off from the Air Force Station, December 5, 2014, in Cape Canaveral, Fla. (Photo by Smiley N. Pool/AP Photo/Houston Chronicle)

Women in Kimono holding an umbrella walk on a street at Ginza shopping district in Tokyo, Japan, March 31, 2016. (Photo by Yuya Shino/Reuters)

A woman sings as Tibetans celebrate the 80th birthday of their spiritual leader, the Dalai Lama, in Kathmandu, Nepal, Monday, July 6, 2015. Around 1,000 monks and other Tibetans gathered at the school compound to celebrate their spiritual leader's birthday. Exiled Tibetans allowed celebrating the Dalai Lama's birthday only inside school compound and refugee camps as long as the facilities do not contain slogans or banners protesting against China. Nepalese government has banned all kinds of Tibetan activities against Chinese rule in Tibet. (Photo by Niranjan Shrestha/AP Photo)

An unidentified runner gestures while being attended by medical services following the first running of the bulls of the San Fermin festival in Pamplona, northern Spain, July 7, 2015. Two runners were gored in the run that lasted 2 minutes and 23 seconds, according to local media. (Photo by Eloy Alonso/Reuters)

Saraa Mutawkil (R), 18, practises boxing at Al Rabie club in Omdurman May 10, 2016. (Photo by Mohamed Nureldin Abdallah/Reuters)