Riot police walk in the street as a couple kiss on June 15, 2011 in Vancouver, Canada. Vancouver broke out in riots after their hockey team the Vancouver Canucks lost in Game Seven of the Stanley Cup Finals. (Photo by Rich Lam/Getty Images)

Coca growers chew coca leaves during a celebration for the reincorporation of Bolivia to the UN Convention Against Illicit Traffic in Narcotic Drugs in La Paz on January 14, 2013. “The coca leaf is not any more seen as cocaine (...), it is a victory of our identity” said Bolivian President Evo Morales. (Photo by Jorge Bernal/AFP Photo)

This combination of two photos taken on July 5, 2014, shows the Aazzab family waiting to break their fast, top, and their meal, bottom, during the holy month of Ramadan in Casablanca, Morocco. For the millions of Muslims abstaining from food and drink from sunrise to sunset every day during Islam's holiest month of Ramadan, that first sip of water after a grueling fast is by far the most anticipated moment of the day. (Photo by Abdeljalil Bounhar/AP Photo)

Beachgoers watch the detonation of a 500 pound British bomb on the beach on May 19, 2014 in Wassenaar, Netherlands. The bomb was dropped by the British allied forces during the second world war over nearby Leiden where it was found on a building site. (Photo by Michel Porro/Getty Images)

A group of Japanese schoolgirls marching in formation during a school visit to the third regiment to experience the soldier's way of life. (Photo by Fox Photos/Getty Images). Circa 1938

“The scientists behind NASA's $2.5 billion Curiosity rover mission on Mars on Tuesday explained the nature of a tiny, gleaming "flower" embedded in Red Planet rock, and revealed where they'll be using the SUV-sized robot's drill for the first time”. – Alan Boyle via NBCNews.com

Photo: Scientists say that a “Martian flower”, seen here in an image from the Curiosity rover's Mars Hand Lens Imager, is a 2-millimeter-wide grain or pebble that's embedded in the surrounding rock. Another, darker-colored mineral grain can be seen above and to the left. (Photo by NASA)

Typhoon Bopha moves toward the Philippines, observed from the ISS, on December 2, 2012. (Photo by AP Photo/NASA via The Atlantic)

A model showcases designs by Antonia Paris during the Women's RTW 3 catwalk during Rosemount Australian Fashion Week Spring/Summer 2011/12 at Overseas Passenger Terminal on May 5, 2011 in Sydney, Australia. (Photo by Stefan Gosatti/Getty Images)