An unknown number of guns are being built with the mechanisms, causing problems for the police and ATF officials. Photo: An ATF agent holds a generic unfinished receiver, back, and one that has been manufactured, front, at an ATF field office in Washington, on May 06, 2014. The ATF is trying to crack down on the trade in the makeshift guns by targeting shops and individuals who offer to turn the unfinished receivers into functional pieces for firearms. (Photo by Bill O'Leary/The Washington Post)

This is the incredible moment a fierce lightning bolt crashed against the Grand Canyon illuminating the steep canyon walls. Shrouded in darkness, the breath-taking landscape was shocked into life as mother nature sent the bolt storming down to Earth. As it cracked against the rocks the bright blue bolt illuminated the South Rim of the canyon, considered one of the Seven Natural Wonders of the World. With just the Desert View Watchtower in the foreground, the lightning was perfectly framed by the canyon which is located in Arizona, USA. (Photo by Travis Roe/U.S. Dept. of the Interior/Caters News)

A visitor poses with a 3D art work during a Japanese Trick Art exhibition at a shopping mall in Jakarta, Indonesia, Tuesday, December 4, 2012. (Photo by Dita Alangkara/AP Photo)

People visit Chinese artist Huang Yongping's installation art work named “Leviathanation” at Tang Contemporary Art of 798 Art District on March 29, 2011 in Beijing, China. The exhibition named “Tracing The Milky Way” will be last until May 14. (Photo by Feng Li/Getty Images)

An art installation formed with milk churns, made by land art artist Gerard Benoit a la Guillaume, is seen at the Chenau de Mayen in the resort of Leysin, Switzerland August 7, 2015. More than 80 milk churns were placed between the Tour d'Ai and the Tour de Mayen summits at an altitude of 2,000 meters (6,561 feet) above sea level under the direction of the artist, to be photographed for his ongoing art project entitled “Milk churns without borders”. (Photo by Denis Balibouse/Reuters)

A tattoo is displayed on the arm of a girl during Bandung Body Art Festival at in Bandung, West Java, on December 7, 2014. Upon its establishment in 2010, founders of the Bandung Body Art Festival sought to celebrate an art form that was once taboo and associated with criminals. Tattoos are now an increasingly acceptable part of Indonesia’s urban landscape, and the annual event this year continued its campaign with 45 tattoo artists offering their services for free at the Ganesha Cultural Center. (Photo by Rezza Estily/JG Photo)

“Liu Bolin is an artist born in China’s Shandong province in 1973, and he earned his Bachelor of Fine Arts from the Shandong College of Arts in 1995 and his Master of Fine Arts from the Central Academy of Fine Arts in Beijing in 2001. His work has been exhibited in museums around the world. Also known as “The Invisible Man”, Liu Bolin's most popular works are from his “Hiding in the City” series; photographic works that began as performance art in 2005”. – Wikipedia. (Photo by Reuters/China Daily)

A visitor looks at a creation by Russian artist Irina Nakhova presented at the Russia's pavilion during the 56th International Art Exhibition (Biennale d'Arte) titled “All the Worlds Futures” on May 5, 2015 in Venice. (Photo by Gabriel Bouys/AFP Photo)