People gather at the site of a bomb explosion in Sanaa December 23, 2014. Five bombs exploded on Tuesday in Sanaa's old quarter, where many supporters of the Shi'ite Muslim Houthi group live, killing at least one person and wounding another, a Yemeni security official said. No one has claimed responsibility for the attacks, but the Houthis have been fighting the Sunni Islamist militant al Qaeda group and allied tribesmen since its gunmen captured Sanaa in September and forced the resignation of a government they had long seen as corrupt. (Photo by Khaled Abdullah/Reuters)

A woman swigs from bottles of rum and coke before entering the Coachella Valley Music and Arts Festival in Indio, California April 12, 2015. (Photo by Lucy Nicholson/Reuters)

Kim Kardashian and Kanye West leave their residence in Paris, on May 23, 2014. (Photo by Kenzo Tribouillard/AFP Photo)

A thrill-seeking storm chaser captured the precise moment these giant lightning bolts lit up dark skies in a series of incredible storms. (Photo by Craig Eccles/Solent News & Photo Agency)

A man tries to photograph the interior of the driver's cab belonging to Eurostar's new Siemens e320 train at St Pancras station in central London, November 13, 2014. Eurostar, the company that runs passenger trains through the Channel tunnel between London and Paris, said it would buy seven additional e320 trains from Siemens for about 300 million pounds ($473 million). The company placed an order for 10 new trains in 2010, the first of which is due to enter commercial service next year, enabling the company to add new routes. (Photo by Andrew Winning/Reuters)

A firefighter uses a saw to open a metal gate while fighting a fire in a convenience store and residence during clashes after the funeral of Freddie Gray in Baltimore, Maryland in the early morning hours of April 28, 2015. (Photo by Eric Thayer/Reuters)

A staff member of Sony Computer Entertainment tries out PlayStation 4's virtual reality headset Project Morpheus at its booth in Tokyo Game Show 2014 in Makuhari, east of Tokyo September 18, 2014. (Photo by Yuya Shino/Reuters)

A cadet lies on the grass after collapsing during a promotion ceremony at a police school in Bogota December 7, 2012. (Photo by John Vizcaino/Reuters)