A health worker dresses in a protective suit before starting to perform the coronavirus testing in an effort to stop the spread of the coronavirus disease (COVID-19) in the Kibera slum of Nairobi, Kenya, May 26, 2020. (Photo by Baz Ratner/Reuters)

Israeli soldiers fire a 155mm self-propelled howitzer towards the Gaza Strip from their position along the border in the southern Israeli city of Sderot on May 20, 2021. Israel is studying whether conditions are right to stop bombing Palestinian militants in Gaza but is preparing for “more days” of strikes if necessary, an Israeli military source said today. Diplomats stepped up efforts today toward a ceasefire to stem 10 days of deadly violence between Israel and armed Palestinian groups in Gaza as air strikes again hammered targets in the enclave. (Photo by Jack Guez/AFP Photo)

People take cover as riot police use pepper spray projectile during a protest as a second reading of a controversial national anthem law takes place in Hong Kong, China on May 27, 2020. (Photo by Tyrone Siu/Reuters)

An Israeli 155mm self-propelled howitzer, loaded on a trailer, arrives at a position along the Israel-Gaza border on May 13, 2021. Israel deployed additional troops to Gaza's border as the military conflict with Palestinian Islamists raged on, while inside Israel security forces scrambled to contain deadly riots between Jews and Arabs. (Photo by Emmanuel Dunand/AFP Photo)

Smoke and flames rise following an Israeli air strike on Gaza City, 18 May 2021. Tensions have escalated in the region, following days of violent confrontations between Israeli security forces and Palestinians in Jerusalem, leading to the heaviest offensive in years. (Photo by Mohammed Saber/EPA/EFE)

Participant Elena Tsagrinou of Cyprus performs during first semi-final of the 2021 Eurovision Song Contest in Rotterdam, Netherlands on May 18, 2021. (Photo by Piroschka Van de Wouw/Reuters)

A masked Burundian protester faces soldiers in front of a burning barricade during an anti-government demonstration against President Pierre Nkurunziza's bid for a third term in the capital Bujumbura, Burundi, 25 May 2015. Street protests continued on 25 May as the United Nations Secretary-General Ban Ki-moon condemned the killing of the leader of the oppsition party Union for Peace and Development (UPD) Zedi Feruzi who opposed Nkurunziza's bid. (Photo by Dai Kurokawa/EPA)

Russians play accordions as they walk near the building of the Federal Security Service (FSB, Soviet KGB successor) in Lubyanskaya Square to mark May Day in Moscow, Russia, Sunday, May 1, 2016. As in Soviet times, about one hundred thousand of cheerful workers paraded across Red Square despite a chilly rain, but instead of red flags with the Communist hammer and sickle, they waved the blue flags of the dominant Kremlin party and the Russian tricolor. (Photo by Alexander Zemlianichenko/AP Photo)