A pilot looks up from a U.S. F-22 Raptor fighter as it prepares to refuel in mid-air with a KC-135 refuelling plane over European airspace during a flight to Britain from Mihail Kogalniceanu air base in Romania April 25, 2016. (Photo by Toby Melville/Reuters)

Turkana tribesmen walk with guns to protect their cattle from rival tribes near Baragoy, Kenya August 4, 2017. (Photo by Goran Tomasevic/Reuters)

Women take part in an annual block party known as “Banda do Candinho e Mulatas” (Candinho Band and Mulatto Women), during carnival festivities at Bixiga neighbourhood in Sao Paulo, Brazil February 7, 2018. (Photo by Nacho Doce/Reuters)

Armed homeowners standing in front their house on Portland Place and confront protesters marching to St. Louis Mayor Lyda Krewson's house in Missouri, U.S. on June 28, 2020. The protesters called for Krewson's resignation for releasing the names and addresses of residents who suggested defunding the police department. (Photo by Laurie Skrivan/St. Louis Post)

A Palestinian horseman rides on the beach at sunset a few hours prior to the new year's celebrations, west of in Gaza city on December 31, 2018. (Photo by Mahmud Hams/AFP Photo)

Secondary school graduates play in a fountain as they celebrate the last day of school, traditionally called the “last bell” in central Kiev, Ukraine on May 31, 2019. (Photo by Valentyn Ogirenko/Reuters)

A woman instructs a boy on how to pose for pictures in front of a mural depicting Soviet pilot Valery Chkalov – who took a non-stop flight over the Arctic and landed in the US state of Washington in 1937 – at Chkalovskaya metro station in Moscow on August 14, 2019. (Photo by Yuri Kadobnov/AFP Photo)

Swiss grass skier Stefan Portmann in action during a free practice at the Grasski World Championships in Marbach, Switzerland, 13 August 2019. About 80 participants from 10 nations will start at the Grasski - World Championships, which will take place from 13th to 18th August 2019. (Photo by Alexandra Wey/EPA/EFE)