A Mai-Mai rebel soldier shows off his guns at a checkpoint near the Mugunga refugee camp in Zaire; 1996. (Photo by Carol Guzy/The Washington Post)

Police officers detain a demonstrator as people protest to defy a ban and march on Taksim Square to celebrate May Day in Istanbul, Turkey on May 1, 2023. (Photo by Dilara Senkaya/Reuters)

Sumo wrestlers of Nishonoseki clan appeal to the winner of a training bout for the next opponent during a joint training session ahead of the May Grand Sumo Tournament in Tokyo May 2, 2015. (Photo by Toru Hanai/Reuters)

Bangladeshi farmers carry harvested produce in a cultivated field ahead of the 14 May World Farmers Day in Chittagong, Bangladesh on May 12, 2022. (Photo by Mohammad Shajahan/Anadolu Agency via Getty Images)

Nursing students attend a capping ceremony on May 10, 2021 in Jinan, Shandong Province of China. International Nurses Day is observed annually on May 12. (Photo by Zhang Yong/China News Service via Getty Images)

An Iranian woman wearing a face mask walks on a street in Tehran, Iran, 19 October 2020. According to the Iranian Health ministry, Iran reported its highest daily COVID-19 death toll of 337 and 4,251 new infections in past 24 hours as it appears that Iran is in a third wave of COVID-19 outbreak. (Photo by Abedin Taherkenareh/EPA/EFE)

A Virgin Atlantic passenger plane flies in the sky with the moon seen in the background, in London, Britain January 19, 2016. (Photo by Toby Melville/Reuters)