Dancers at the Windmill Theatre in London, England practice a routine wearing gas masks and hard-hats with their costumes, 1940. (Photo by Hulton Archive/Getty Images)

People watch Russian heavy weapons at Tverskaya street during the rehearsal of the Victory Day parade in Moscow, Russia, 04 May 2022. Victory Day is held annually on 09 May and marks the defeat of Nazi Germany in 1945. (Photo by Yuri Kochetkov/EPA/EFE)

A Palestinian man sits on a damaged car following Israeli airstrikes on Jabaliya refugee camp, northern Gaza Strip, Thursday, May 20, 2021. Heavy airstrikes pummeled a street in the Jabaliya refugee camp in northern Gaza, destroying ramshackle homes with corrugated metal roofs nearby. The military said it struck two underground launchers in the camp used to fire rockets at Tel Aviv. (Photo by Khalil Hamra/AP Photo)

A woman wearing a face mask to help protect against the spread of the new coronavirus crosses a stream in Seoul, South Korea, Wednesday, July 15, 2020. (Photo by Lee Jin-man/AP Photo)

Military chaplain Yurii looks on in a trench after an Orthodox Easter service for Ukrainian servicemen at their position, as Russia's attack on Ukraine continues, in Kharkiv region, Ukraine on April 15, 2023. (Photo by Sofiia Gatilova/Reuters)

A couple kisses in a central Barcelona street during the first night without the state of alarm, on 9 May, 2021 in Barcelona, Catalonia, Spain. The state of alarm that the Government decreed for the second time six months ago ended at 00.00 hours this Sunday, May 9. In Catalonia this has led to the fall of the curfew and the perimeter confinement of the Community. (Photo By Lorena Sopena via Getty Images)

In this photo taken on Saturday, May 2, 2020, funeral workers, wearing protective suits, lower the coffin of Semen Muchka, 71, who died of coronavirus disease, into the grave at a cemetery in Krynytsya, Ukraine. (Photo by Evgeniy Maloletka/AP Photo)

People look through the front windshield of a damaged trolleybus in Donetsk, January 22, 2015. At least seven civilians were killed on Thursday when a shell or a mortar hit a trolleybus stop in the rebel-controlled city of Donetsk in eastern Ukraine, a Reuters witness said. The Reuters cameraman said he saw six bodies on the ground near, and inside, a trolleybus in a southern district of the city. Windows of shops nearby had been blown out by the blast. (Photo by Alexander Ermochenko/Reuters)