A woman waits to hear about her sister, a teacher, following a shooting at the Sandy Hook Elementary School in Newtown, Connecticut. A man killed his mother at their home and then opened fire inside the elementary school where she taught, massacring 26 people, including 20 children, as youngsters cowered in fear to the sound of gunshots reverberating through the building and screams echoing over the intercom. (Photo by Jessica Hill/Associated Press)

A man cries as he carries his daughter while walking from an Islamic State-controlled part of Mosul towards Iraqi special forces soldiers during a battle in Mosul, Iraq March 4, 2017. Reuters Photographer Goran Tomasevic: “Both screaming in terror, a father and the young daughter he cradled in his arm fled through the rubble-strewn streets of Wadi Hajar, transformed in a flash into a battleground between Islamic State fighters and Iraqi special forces. They and their neighbours – some wearing rubber sandals, some barefoot – were running from an IS counter-attack in this part of Mosul, dodging gunfire as the militants closed in”. (Photo by Goran Tomasevic/Reuters)

Iraqi troops fire artillery towards Islamic State (IS) group jihadists' positions in west Mosul on March 11, 2017 during the ongoing battle to retake the city from the group. (Photo by Aris Messinis/AFP Photo)

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

Samurai commiting seppuku (hara-kiri) in Japan, circa 1880. (Photo by adoc-photos/Corbis via Getty Images)

To draw the public's attention to a new line of bathing suits, a Tokyo department store used live models to show off the suits on June 5, 1950. The rain didn't bother the curious, and both the girls and the crowd seemed to like the idea of staring at each other through the glass. (Photo by AP Photo via The Atlantic)

A dog takes a rest under a destroyed house at a site where a landslide swept through a residential area at Asaminami ward in Hiroshima, western Japan, August 20, 2014. At least 36 people, including several children, were killed in Japan on Wednesday, when landslides triggered by torrential rain slammed into the outskirts of the western city of Hiroshima, and the toll could rise further, police said. Seven people were missing after a month's worth of rain fell overnight, loosening slopes already saturated by heavy rain over the past few weeks. (Photo by Toru Hanai/Reuters)

Women dressed as nuns pose for pictures during Halloween celebrations in the Shibuya district in Tokyo, Japan October 31, 2015. (Photo by Thomas Peter/Reuters)