Models struggle against strong wind before the rehearsal of Christian Dior's Haute Couture Spring-Summer 2017 live show to celebrate Dior's new flagship store at the rooftop of Ginza Six mall in Tokyo, Japan, April 19, 2017. (Photo by Toru Hanai/Reuters)

A US Army M1A2 SEP tank participates in the Strong Europe Tank Challenge 2017 at the military training area in Grafenwoehr, Germany, 12 May 2017. Six North Atlantic Treaty Organization (NATO) nations and partner nations, Austria, France, Germany, Poland, Ukraine and the USA are taking part in this competing exercise. (Photo by Christian Bruna/EPA)

Satrio smokes at a kiosk after elementary school on March 3, 2017 in Yogyakarta, Indonesia. Satrio has smoked up to one pack a day and began when he was six years old. (Photo by Ulet Ifansasti/Getty Images)

People look at the Turrialba volcano as it spewes ashes on May 20, 2016, in Cartago, Costa Rica. The Turrialba volcano started erupting columns of smoke and ash that the wind extended towards the Costa Rican capital, in what according to experts is the strongest eruption in the past six years. (Photo by Ezequiel Becerra/AFP Photo)

Flashmob: Water Battle on All-Russian Exhibition Center in Moscow, Russia, on August 5, 2012. (Photo by Lilja Dal)

Eight-year-old Niu Dongfang trains at the No. 2 Beijing Shuangqiao School January 13, 2005 in Beijing, China. Most of students in the gymnastics school have to study more than five years from as young as age six before they become athletes. (Photo by Guang Niu/Getty Images)

Seized plastic handguns which were created using 3D printing technology are displayed at Kanagawa police station in Yokohama, south of Tokyo, in this photo taken by Kyodo May 8, 2014. Yoshimoto Imura became the first man to be arrested in Japan for illegal possession of two guns he created himself using 3D printing technology, Japanese media said on Thursday. The 27-year-old, a college employee in the city of Kawasaki, was arrested after police found video online posted by Imura claiming to have produced his own guns. Gun possession is strictly regulated in Japan. Police raided Imura's home and found five guns, two of which could fire real bullets, Japanese media said. (Photo by Reuters/Kyodo)