Men stage an attack during a training session for the Olympic Torch Security Team who will be protecting the torch bearers and Olympic flame during the torch relay's progress through the UK, at the Metropolitan Police Training School on March 9, 2012 in London, England. (Photo by Lewis Whyld – WPA Pool /Getty Images)

Ukrainian police detain activists of women's rights group Femen as they protest against homophobia outside the parliament building in Kiev, Ukraine, November 12, 2015. Femen and gay rights activists are pushing parliament to adopt bills, including one that would ban discrimination in the workplace based on sexuality, which is included in a package of laws to liberalise Ukraine's visa regime with the EU. (Photo by Gleb Garanich/Reuters)

A doll, placed by stranded Iranian migrant protesters, hangs from barbed wire in front of Madedonian police at the Greek-Macedonian border near to the Greek village of Idomeni November 29, 2015. The protesters were demonstrating against what they say is the closure of the border for Iranian migrants. According to the demonstrators, the hanging toys and dolls represent the outcome of being unable to return, if they are sent back to Iran. (Photo by Yannis Behrakis/Reuters)

Germany's Wolfgang Kimmig-Liebe, who has been volunteering as Santa Claus for years, is searched by a Carabiniere paramilitary police officer before entering in St. Peter's Square at the Vatican to attend Pope Francis general audience, Wednesday, December 2, 2015. (Photo by Alessandra Tarantino/AP Photo)

A police officer removes a reveler from standing on a post as they guard and clear the street of revelers dressed in holiday themed costumes during SantaCon in New York Saturday, December 12, 2015. As thousands of Santa-suited merrymakers prepare to hit the city's streets and bars, organizers of the annual pub crawl say they're taking more steps than ever to deter naughty behavior. (Photo by Andres Kudacki/AP Photo)

A biker poses on his Bousouzoku motorbike at the Dangouzaka rest stop in Yamanashi, west of Tokyo, Japan, January 3, 2016. Police on Sunday halted a group of about two dozen Bousouzoku bikers who paraded their noisy motorcycles during an annual New Year outing in the Mount Fuji region. This Japanese motorcycle subculture dated back to the 1950s and regularly chafes with the police because of their provocative traffic behaviour and bike customising, that is often deemed illegal. (Photo by Thomas Peter/Reuters)

A man carries a bag on his back in Guangzhou, Guangdong province, January 26, 2016. According to traffic police, over 2.9 billion trips will be made around China during the 40-day Spring Festival travel rush, which started on January 24. (Photo by Reuters/Stringer)

A woman runs while another woman ducks down to avoid teargas as police disperse supporters of the opposition Coalition for Reforms and Democracy (CORD), led by former Prime Minister Raila Odinga, during a demonstration against Independent Electoral and Boundaries Commission (IEBC) in downtown Nairobi, Kenya, 09 May 2016. (Photo by Dai Kurokawa/EPA)