A prototype battery-powered plane, called Greased Lightning or GL-10 is pictured flying at NASA's Langley Research Center in this undated handout photo obtained by Reuters May 1, 2015. The plane, which has 10 engines and can take off like a helicopter and fly efficiently like an aircraft, is currently in the design and testing phase. (Photo by Reuters/NASA)

A man fires a weapon as he dances during a traditional excursion near the western Saudi city of Taif, August 8, 2015. Saudis usually party in such excursions as they celebrate weddings or graduations. (Photo by Mohamed Al Hwaity/Reuters)

A reveller dressed as Spider-Man takes part in a presentation at the top of a building during an annual block party known as “Enquanto isso na Sala da Justiça” (Meanwhile, in the justice room), one of the many carnival parties taking place in the neighbourhood of Olinda, Brazil February 7, 2016. (Photo by Ueslei Marcelino/Reuters)

Indian Air Force soldiers toss their rifles as they perform during the full-dress rehearsal for Indian Air Force Day at the Hindon air force station on the outskirts of New Delhi October 6, 2015. (Photo by Anindito Mukherjee/Reuters)

Russian artist Maria Gazanova (L) works on her "The Alive Painting" art work during the Art Krasnoyarsk annual festival in Siberian city of Krasnoyarsk, Russia November 4, 2015. (Photo by Ilya Naymushin/Reuters)

A commuter gestures to Boris Johnson as he rides across Vauxhall Bridge in London, England on November 19, 2015. The London mayor was opening a cycle superhighway. (Photo by John Stillwell/PA Wire)

Mug shot of William Stanley Moore, 1 May 1925, Central Police Station, Sydney. This picture appears in the Photo Supplement to the NSW Police Gazette, 28 July, 1926 captioned: “Opium dealer. Operates with large quantities of faked opium and cocaine. A wharf labourer; associates with water front thieves and drug traders”. (Photo by NSW Police Forensic Photography Archive, Justice & Police Museum, Histiric Houses Trust of NSW)

A woman rides a donkey during a donkey race in Roum village, Jizeen countryside, southern Lebanon, August 9, 2015. (Photo by Ali Hashisho/Reuters)