A tearful Beatle lover pleads unsuccessfully with a policeman to carry her fan button to Ringo, one of the four mop-top singers who drew squeals and shrieks from more than 30,000 spectators at two Indiana State Fair shows in Indianapolis on September 4, 1964. (Photo by Bob Daugherty/AP Photo)

In this April 4, 2014 file photo, a community policeman kicks a man who they alledge participated in an ambush against them near the town of La Concepcion, Mexico. The vigilante force was set-up by affected communities opposed to the construction of the La Parota hydroelectric dam. Two vigilantes were injured and one died. (Photo by Bernandino Hernandez/AP Photo)

Getting her tongue pierced was “exciting and scary” says a teen who succumbed to pressure from her best friend in Austin, Texas, February 22, 2008. This image is featured in National Geographic's exhibition “Women of Vision: National Geographic Photographers on Assignment”, on view at the Palm Beach Photographic Centre, Jan. 22 - Mar. 22, 2015. (Photo by Kitra Cahana/National Geographic)

Polar bear twins make their first public appearance with their mother “Freedom” at Ouwehands Zoo Rhenen, in Rhenen, The Netherlands, 19 February 2015. The twins, who were born in November 2014, have not been named because their gender has not yet been determined. (Photo by Bart Maat/EPA)

Handout grab taken from YouTube of Commander Chris Hadfield who has said goodbye to life on the International Space Station by making a cover version of David Bowie's Space Oddity. Issue date: Monday May 13, 2013. (Photo by Commander Chris Hadfield/YouTube/PA Wire)

The student Patricia Vasconcellos de Almeida, 22, tried to kiss one of the military police who formed a cordon ostensibly in front of the building Fetranspor (Federation of Transport Companies), in Rio de Janeiro, on June 27, 2013. (Photo by Zulmair Rocha/UOL)

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)

“A Brazilian hotel was evacuated in the capital, Brasilia, on Monday after a man took hostage an employee who was held for hours before he was safely released to police. Firefighters and police cordoned off the area and about 300 guests and other employees left the hotel – some reportedly told to leave by the man who took the employee hostage”. – Associated Press. (Photo by Evaristo Sa/AFP Photo)