A participant learns to throw a grenade during a military exercise for civilians conducted by members of the Georgian National Legion paramilitary volunteer unit amid threat of Russian invasion in Kyiv, Ukraine on February 4, 2022. (Photo by Serhii Nuzhnenko/Reuters)

An undated archive picture shows a dog pulling a Belgian machine gun at an unknown location in northern France. A Viscount in the Armoured Cavalry Branch of the French Army left behind a collection of hundreds of glass plates taken during World War One (WWI) that have never before been published. The images, by an unknown photographer, show the daily life of soldiers in the trenches, destruction of towns and military leaders. The year 2014 marks the 100th anniversary of the start of WWI. (Photo by Collection Odette Carrez/Reuters)

A relative of a victim of the Ukraine International Airlines PS 752 plane that crashed after taking off from Tehran's Imam Khomeini airport reacts at Boryspil International Airport, outside Kiev, Ukraine on January 8, 2020. (Photo by Serhii Nuzhnenko/Reuters)

People in quarantine exercise in front of their homes amid Covid-19 full lockdown of the city in Shanghai, China, 27 April 2022. According to the Shanghai Health Commission on 27 April, there were 48 new Covid-19 deaths, 1,606 locally transmitted cases, and 11,956 local asymptomatic infections, in Shanghai city. Despite the death toll rising in Shanghai, the number of daily infections has gradually declined. (Photo by Alex Plavevski/EPA/EFE)

Claire McGuire (C) smiles after winning the women's snowboard division of the Bikini & Board Shorts Downhill at Crystal Mountain, a ski resort near Enumclaw, Washington April 19, 2014. Skiers and snowboarders competed for a chance to win one of four season's passes. (Photo by David Ryder/Reuters)

Children play in an outdoor shower as a soldier takes part in a surprise operation in the Manguinhos slum in Rio de Janeiro, Brazil, Thursday, January 18, 2018. Troops have been sent to Rio due to the increase of the violence, and in an attempt to help restore order, but so far have had little impact. The operation on Thursday took place three weeks ahead of Carnival, when thousands of tourists are expected to arrive in the city. (Photo by Leo Correa/AP Photo)

New York City policemen tangled with demonstrators at a subway station on the opening day of the New York World's Fair, April 22, 1964. Youths attempted to stall the train, which was headed from the city to the fairgrounds, as a form of protest on behalf of civil rights for blacks. (Photo by Charles Gorry/AP Photo)

Workers lay railway track in a tunnel of the Crossrail project in Stepney, east London, Britain, November 16, 2016. Crossrail, which is Europe's largest construction project, is a railway link which will connect outlying areas to the east and west of London with tunnels under the centre of the capital. (Photo by Stefan Wermuth/Reuters)