Demonstrators wear skull masks during an anti government protest, as Chile's President Michelle Bachelet delivers a speech inside the National Congress, in Valparaiso city, Chile May 21, 2016. (Photo by Ivan Alvarado/Reuters)

A pro-government supporter scuffles with an anti-extradition supporter outside the office of pro-China lawmaker Junius Ho in Tsuen Wan in Hong Kong, China on July 22, 2019. Hong Kong demonstrators gathered for another weekend of protests against the controversial extradition bill and with a growing list of grievances, maintaining pressure on Chief Executive Carrie Lam. (Photo by Edgar Su/Reuters)

Demonstrators take part in a mass anti-Putin rally on December, 24, 2011 in Moscow, Russia. Tens of thousands of demonstrators rallied in cities across Russia to protest alleged vote fraud in recent parliamentary elections and to express their discontent with Prime Minister Vladimir Putin, leader of the dominant United Russia party. (Photo by Alexander Aleshkin/Epsilon/Getty Images)

Photo by: Rustem Adagamov; Source: LiveJournal

Anti-pollution protesters wearing traditional costumes and contemporary gas masks ride bicycles in the Qingming Grand river park in Kaifeng, Henan Province, China on January 1, 2017. The Beijing Municipal Environmental Protection Bureau extended an “orange alert” for heavy air pollution for three more days. (Photo by SIPA Asia/Rex Features/Shutterstock)

Russian marines attached to the anti- submarine ship Admiral Tributs show their skills during a demonstration at a park in Manila on January 5, 2017, as part of their five- day port- of- call activities in the country' s capital. (Photo by Ted Aljibe/AFP Photo)

Police detain a woman protesting against the court verdict for Yuliy Boyarshinov, and Viktor Filinkov, members of a left-wing group Set (Network) at the Western regional military court in St.Petersburg, Russia, Monday, June 22, 2020. A Russian military court convicted two members of a left-wing youth group of terrorism Monday and sentenced them to prison terms of five and a half and seven years, in a case that human rights groups called fabricated and based on coerced testimony. (Photo by Dmitri Lovetsky/AP Photo)

Pilot Commissioner Ozge Karabulut prepares to take off during World Pilots Day in Ankara, Turkiye on April 25, 2022. Pilot Commissioner Ebru Melek (not seen) who has been involved in the fight against criminals, especially terrorism, within the body of the Aviation Department of the General Directorate of Security, which has ensured peace and security in the skies of the homeland for 41 years with aircraft, of Turkish Police Service and Turkiye's the first female attack helicopter Pilot Commissioner Ozge Karabulut celebrate her colleagues World Pilots' Day on April 26th. (Photo by Aytac Unal/Anadolu Agency via Getty Images)

Some of London's telephone operators and engineers, trying out their gas masks at the anti-gas civilian training centre in Gloucester, where they were taught how to deal with gas attacks. (Photo by Harry Todd/Fox Photos/Getty Images). 13th February 1937