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 Chinese man wears a mask to protect against pollution as he waits at a red light while commuting to work in heavy smog on December 8, 2015 in Beijing, China. The Beijing government issued a 'red alert' for the first time since new standards were introduced earlier this year as the city and many parts of northern China were shrouded in heavy pollution. Levels of PM 2.5, considered the most hazardous, crossed 400 units in Beijing, lower than last week, but still nearly 20 times the acceptable standard set by the World Health Organization. The governments of more than 190 countries are meeting in Paris to set targets on reducing carbon emissions in an attempt to forge a new global agreement on climate change. (Photo by Kevin Frayer/Getty Images)

This undated handout image courtesy of the San Diego Zoo Wildlife Alliance shows “Pat”, a Pacific pocket mouse fondly named after actor Sir Patrick Stewart. A mouse named after “Star Trek” actor Patrick Stewart is officially the world's oldest in captivity, a US zoo has announced Pat the Pacific Pocket Mouse – the smallest species of mouse in North America – bagged the title when he hit nine years and 209 days old on February 8, 2023. (Photo by Ken Bohn/San Diego Zoo Wildlife Alliance via AFP Photo)

Artists perform during the traditional costume parade during the 190th edition of the Oktoberfest beer festival in Munich, southern Germany on September 21, 2025. The world's biggest beer festival Oktoberfest runs until October 5, 2025. (Photo by Michaela Stache/AFP Photo)

Women offer prayers on Valentines Day at the Trimurti Shrine, which is believed to bring love, in Bangkok on February 14, 2023. (Photo by Manan Vatsyayana/AFP Photo)

Artists perform during the 137th Nice Carnival parade in Nice, southeastern France, on February 19, 2022. The Carnival takes place until February 27, 2022 on the theme “King of animals”. (Photo by Valery Hache/AFP Photo)

“Exactly one year before the long awaited Sochi Olympics, Vladimir Putin went to Sochi personally to see how the construction is going. After receiving a report saying the ski jumps that were supposed to be ready in 2011, are not completed still, while their price has sky-rocketed from 1.2 billion to 8 billion roubles, he commented, “Good for you. Good job”, and then fired the vice president of the Olympic committee. Russian artist Vasily Slonov painted his view of the upcoming games, giving a new interpretation to the adored Russian mascot Cheburashka, and combining officially endorsed stereotypes of Russia with grimmer and less accepted ones”. – Ruskie.info. (Photo by Vasily Slonov)

A man takes a photo of a radio antenna that's part of the Atacama Large Milimeter Array Observatory on March 12, 2013 at Llano de Chajnantor, about 43 miles (70 kilometers) from San Pedro de Atacama, Chile. The $1.5 billion ALMA facility, which had its official inauguration on March 13, is considered the world's most expensive ground-based observatory. (Photo by Felipe Trueba/EPA)