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)

Tourists take a “selfie” as demonstrators burn a trash container during a May Day rally in Barcelona, Spain, on May 1, 2014. Tens of thousands of workers marked May Day in European cities with a mix of anger and gloom over austerity measures imposed by leaders trying to contain the eurozone's intractable debt crisis. (Photo by Manu Fernandez/Associated Press)

The granddaughter of one of the family members cries after the eviction from their home in El Raval neighbourhood, amid the coronavirus disease (COVID-19) pandemic, in Barcelona, Spain, May 12, 2021. (Photo by Nacho Doce/Reuters)

Victoria of Bulgaria performs during the second semi-final of the 2021 Eurovision Song Contest in Rotterdam, Netherlands, May 20, 2021. (Photo by Piroschka van de Wouw/Reuters)

A group of San Bushmen from the Khomani San community practice their hunter-gatherer craft in the Southern Kalahari desert on October 15, 2009 in the Kalahari, South Africa. One of the largest studies of African genetics by an international team from the University of Pennsylvania, published in April 2009, revealed that the San of Southern Africa are the most genetically diverse on earth, and that the San homeland could be the spot where modern humanity began. (Photo by Dan Kitwood/Getty Images)

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)

Local youth representatives dressed a Stormtrooper and Darth Vader (L-in black) from the Star Wars film franchise patrol in a wooden boat around a submerged village to remind residents to stay at home during the enhanced community quarantine in suburban Manila on May 6, 2020, as part of government's efforts to combat the spread of the COVID-19 coronavirus. (Photo by Ted Aljibe/AFP Photo)

A nurse at St. Joseph's Hospital wears a unique mask as the hospital celebrates the release of a COVID-19 patient after 45 days in their care during the outbreak of the coronavirus disease (COVID-19) in Orange, California, U.S., May 5, 2020. (Photo by Mike Blake/Reuters)