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)

Russian President Vladimir Putin, center, uses a binocular, as Defense Minister Sergei Shoigu, left, and chief of Russia's military's General Staff Valery Gerasimov, right, observe military exercises near the Baikal Lake on Wednesday, July 17, 2013. (Photo by Alexei Nikolsky/AP Photo/RIA Novosti/Presidential Press Service)

In this August 21, 2017 photo released by the U.S. Defense Department, Qatari special operations personnel conduct a military free-fall Friendship Jump over Qatar. The U.S. military has halted some exercises with its Gulf Arab allies over the ongoing diplomatic crisis targeting Qatar, trying to use its influence to end the monthslong dispute, authorities told The Associated Press on Friday, October 6, 2017. (Photo by Staff Sgt. Trevor T. McBride/ U.S. Air Force via AP Photo)

“Derby”, Kentucky Gallahue's goldendoodle, of Point Loma, sporting a mohawk haircut and sunglasses, leaps off the surfboard during the 2018 Imperial Beach Surf Dog Competition next to the Imperial Beach Pier in San Diego, California on July 28, 2018. (Photo by Howard Lipin/San Diego Union-Tribune via ZUMA Press/Rex Features/Shutterstock)

A pedestrian leaps across a flooded portion of the La Paz and Seventh Street intersection as a winter storm arrived, Thursday, December 6, 2018 in Victorville, Calif. The second round of a fall storm dumped snow and rain that jammed traffic on Southern California highways and loosened hillsides in wildfire burn areas on Thursday. (Photo by James Quigg/The Daily Press via AP Photo)

Traditional dancers from southern state Tamil Nadu prepare themselves as they wait to perform during a press preview of displays being featured for the upcoming Republic Day parade in New Delhi on January 22, 2019. The Republic Day is an annual showcase of India's military hardware and cultural diversity. India celebrates its 70th Republic Day on January 26. (Photo by Sajjad Hussain/AFP Photo)

A staff member of Yutian County poses for a video on marigold industry at an agricultural industrial park in Yutian County, northwest China's Xinjiang Uygur Autonomous Region, September 20, 2020. As one of the five counties in Hotan Prefecture that have not been lifted out of poverty, Yutian County is accelerating its steps to shake off poverty by planting marigold. (Photo by Chine Nouvelle/SIPA Press/Rex Features/Shutterstock)

A former Gurkha (special forces soldier), Nirmal Purja, takes a selfie at the start of his attempt to scale the world’s 14 highest peaks in seven months to break a 31-year-old record. Nirmal Purja, known as Nims, aims to smash the current record – which stands at seven years, 11 months and 14 days – set by Polish climber Jerzy Kukuczka. On the way, he also plans to defeat at least seven speed world records on mountains over 8,000m high. (Photo by Nirmal Purja/PA Wire Press Association)