Serbian police officers of the Special Anti-Terrorist Unit pose for a picture in their base outside Belgrade October 8, 2014. When the killing of an unarmed black teenager by a white policeman in Ferguson, Missouri, in August sparked sometimes violent protests, the response of police in camouflage gear and armoured vehicles wielding stun grenades and assault rifles seemed more like a combat operation than a public order measure. Some U.S. police departments have recently acquired U.S. military-surplus hardware from wars abroad, but there are many law enforcers around the world whose rules of engagement also allow the use of lethal force with relatively few restrictions. But for every regulation that gives police wide scope to use firearms, there is another code that sharply limits their use. In Serbia, police may use measures ranging from batons to special vehicles, water cannon and tear gas on groups of people who have gathered illegally and are behaving in a way that is violent or could cause violence, but they may use firearms only when life is endangered. (Photo by Marko Djurica/Reuters)

A woman walks past murals adorning the walls of Garibaldi subway station, in Milan, Friday, February 28, 2020. Due to the COVID-19 virus outbreak in northern Italy, the bustling metropolis of Milan has resembled more of a ghost town lately, as workers stayed home and tourism has dwindled there, and other parts of Italy. (Photo by Luca Bruno/AP Photo)

Erica Daly, a District Nurse Team Leader at Mersey Care NHS, stands in front of the “Liver Bird Wings”, an artwork by Paul Curtis on a wall within Liverpool's Baltic Triangle on April 29, 2020. (Photo by Peter Byrne/PA Images via Getty Images)

A food market shows off rows upon rows of dead animals, some of which have been beaten to death. Dogs and chickens can be seen lined up with their mouths hanging wide open. Shoppers even pick up some of the dogs and bats as they look for the best on the market. Retired biologist and amateur photographer Alf Jacob Nilsen took the shocking pictures of the market during a visit to Tomohon Village in Northern Sulawei, Indonesia. Pictured: Flying foxes (bats) for sale at the market. (Photo by Alf Jacob Nilsen/Solent News)

A woman wearing a protective face mask walks past a graffiti, after authorities eased lockdown restrictions that were imposed to slow the spread of the coronavirus disease (COVID-19), in Mumbai, India, June 12, 2020. (Photo by Hemanshi Kamani/Reuters)

People carry lychee for sale on a motorbike on a street in Luc Ngan, Bac Giang province, Vietnam, 22 June 2016. Lychee output in Bac Giang province is expected to reach 130,000 tonnes this year. China is still Vietnam's main lychee export market so far, buying around 60 percent of the annual crop, according to official reports. (Photo by Luong Thai Linh/EPA)

A labourer carries a basket of bananas inside a wholesale fruit and vegetable market in Bengaluru, India, August 22, 2016. (Photo by Abhishek N. Chinnappa/Reuters)

A girl walks in front of a graffiti painted on the wall of a house located inside the 15th-century complex built by Mameluk Sultan al-Ashraf Qaitbey, in Cairo's City of the Dead, Egypt February 13, 2017. (Photo by Amr Abdallah Dalsh/Reuters)