Riot police clash with protesters during a rally to demand a referendum to remove Venezuela's President Nicolas Maduro in Caracas, Venezuela, September 1, 2016. (Photo by Marco Bello/Reuters)

An F/A-18 Hornet assigned to Strike Fighter Squadron One Five One (VFA-151) emerges from a cloud created when it broke the sound barrier in the skies over the Pacific Ocean, July 7, 1999. (Photo by John Gay/US Navy)

Police walk past a burning car during riots in Birmingham City Centre on August 8, 2011 in Birmingham, England. After three nights of rioting and looting in and around London, the chaos is starting to spread to other cities around Britain. (Photo by Jeff J Mitchell/Getty Images)

A marcher dressed as Marilyn Monroe during the annual Gay Pride march in London, July 1994. (Photo by Steve Eason/Hulton Archive/Getty Images)

Devotees attend the annual voodoo festival in Ouidah January 10, 2016. The national voodoo holiday in the West African country of Benin had a distinctively political accent this year as practitioners from Africa and the Americas gathered on Sunday to offer prayers and sacrifices for peace. Hundreds of followers of the traditional religion gathered in the Atlantic coast town of Ouidah, once an important port in the slave trade, to pray for calm during the tiny country's presidential election scheduled for February. (Photo by Akintunde Akinleye/Reuters)

A hand of a devotee is pictured as she rings a bell while offering prayers to the chariot of God Bhairab during the Bisket festival in Bhaktapur, Nepal, April 13, 2016. During the festival, also regarded as Nepalese New Year, images of the Hindu god Bhairava and his female counterpart Bhadrakali are enshrined in two large chariots and pulled to an open square after which rituals and festivities are performed. (Photo by Navesh Chitrakar/Reuters)

A mother of a victim who was onboard sunken ferry Sewol, leaves a message on a desk used by her child at an empty classroom, which was preserved since the disaster, at Danwon high school during the second anniversary of the disaster in Ansan, South Korea, April 16, 2016. (Photo by Kim Hong-Ji/Reuters)

Participants wearing historical attire compete on historical high wheel Penny Farthing bicycles in the traditional 'One Mile Race' at Letna Park in Prague, Czech Republic, November 7, 2015. The meeting of Penny Farthing bicycles is taking place for the 22th time. (Photo by Filip Singer/EPA)