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)

An employee holds a plant with roots at the Plant Advanced Technologies (PAT) company greenhouse in Laronxe near Nancy, Eastern France, June 19, 2015. The farmers employed at the site in Laronxe are growing plants in a special way with a view to “milking” them for use in medicines, cosmetics and agrochemicals. Several major brands, including Germany's BASF and France's Chanel, have teamed up with Plant Advanced Technologies (PAT) in the hope of securing privileged access to the so-called “biomolecules” it extracts through the use of a patented technique. (Photo by Vincent Kessler/Reuters)

A couple wearing masks as a precaution against the spread of the new coronavirus walk on the Malecon seawall at sunset in Havana, Cuba, Monday, August 31, 2020. Cuban authorities will introduce new measures starting tomorrow Tuesday aimed at containing the spread of the coronavirus in Havana among others a curfew from 7 pm until 5 am and no one without special permission will be able to enter or leave the province. The new measures will last at least 15 days. (Photo by Ramon Espinosa/AP Photo)

Handlers control the giant puppet MOCCO during a special training session in Takamori, Nagano prefecture, Friday, April 23, 2021. Tokyo 2020 organizers created about 10 meter-tall puppet to symbolize the spirit of the people from the regions affected by the 2011 earthquake and tsunami. The puppet will travel from Tohoku to Tokyo in May to be in place for the games scheduled to open in July. (Photo by Koji Ueda/AP Photo)

Special Merit Award. Mallory Franklin (2019). The British slalom canoeist has competed internationally since 2009 and won nine medals in total at the ICF Canoe Slalom World Championships with four golds, four silvers and a bronze. She has also won eleven medals at the European Championships. (Photo by Richard Pelham/World Sports Photography Awards 2021)

Russian servicemen display military camouflage equipments during the joint military anti-terrorist command and staff exercise of the armed forces of the Shanghai Cooperation Organization member states Peace Mission-2021 at the Donguz training ground in the Orenburg region, Russia, 23 September 2021. More than 3.4 thousand servicemen from Russia, India, China, Pakistan, Tajikistan, Uzbekistan, Kazakhstan, Kyrgyzstan and more than 600 units of weapons, military and special equipment are involved in the exercise Peace Mission-2021. (Photo by Maxim Shipenkov/EPA/EFE)

Todd Bretl specializes in underwater photography, and is able to capture striking photos of aquatic life big and small. His photos of sharks are particularly striking; though he rarely faces hostility from the animals, he tries not to spend too much time looking through his viewfinder and many shots are framed by educated guesses and impeccable timing. What follows are photographs taken over the past several years on trips to the Bahamas and Isla Guadalupe, an island off the coast of the Baja California peninsula in Mexico. (Photo by Todd Bretl)

Dan McManus and his service dog Shadow hang glide together outside Salt Lake City, Utah, July 22, 2013. McManus suffers from anxiety and Shadow's presence and companionship help him to manage the symptoms. The two have been flying together for about nine years with a specially made harness for Shadow. (Photo by Jim Urquhart/Reuters)