A demonstrator shows her arm with the name “Marielle” written on it, as she performs during a protest against the murder of councilwoman Marielle Franco in Rio de Janeiro, Brazil, Tuesday, March 20, 2018. Franco's murder came just a month after the government put the military in charge of security in Rio, which is experiencing a sharp spike in violence less than two years after hosting the 2016 Summer Olympics. (Photo by Leo Correa/AP Photo)

South Vietnamese forces escort suspected Viet Cong officer Nguyen Van Lem (also known as Bay Lop) on a Saigon street February 1, 1968, early in the Tet Offensive. Moments later, Lem was executed by Gen. Nguyen Ngoc Loan, chief of the national police. (Photo by Eddie Adams/AP Photo)

Dancers from Tokyo wearing traditional costumes perform during a celebration event, a day before Japan's Emperor Naruhito and Empress Masako's royal parade in front of the Imperial Palace in Tokyo, Japan November 9, 2019. (Photo by Issei Kato/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)

A sculpture made by activists on Lambeth bridge during the Extinction Rebellion protest in London, England on October 7, 2019. (Photo by Henry Nicholls/Reuters)

Soldiers evacuate a hostage from a mass shooting scene at the Terminal 21 shopping mall in Nakhon Ratchasima, Thailand, 09 February 2020. According to media reports, at least 21 people were killed, and as many as 30 wounded after a Thai soldier, identified as 32-year-old Jakraphanth Thomma, went on a shooting rampage with a M60 machine gun in the city of Nakhon Ratchasima, also known as Korat. Thomma held an unknown number of people hostage within the Terminal 21 shopping mall for around 17 hours before being shot and killed in a police operation. (Photo by Rungroj Yongrit/EPA/EFE)

A man wears a gas mask as he holds a bouquet of flowers, following the outbreak of the novel coronavirus on Valentine’s Day in Hong Kong, China on February 14, 2020. (Photo by Tyrone Siu/Reuters)

A local farmer Theophilus Mwendwa runs through a swarm of desert locusts to chase them away in the bush near Enziu, Kitui County, some 200km east of the capital Nairobi, Kenya, 24 January 2020. Large swarms of desert locusts have been invading Kenya for weeks, after having infested some 70 thousand hectares of land in Somalia which the United Nations Food and Agriculture Organisation (FAO) has termed the “worst situation in 25 years” in the Horn of Africa. FAO cautioned that it poses an “unprecedented threat” to food security and livelihoods in the region. (Photo by Dai Kurokawa/EPA/EFE)