A member of the Fuerza Civil (Civil Force) police unit takes part in a simulated crime situation during a media presentation to show the police model that the federal government wants for the rest of the country, at the police academy in Monterrey December 17, 2014. Fuerza Civil, a tactical team of the police unit trained by the army, was created by the Nuevo Leon government in 2011 to curb down corruption and infiltration by drug gangs in the police corps, local media reported. Promising a new law to stop the infiltration of local governments by organized crime, President Enrique Pena Nieto pledged to reform the penal system and send an proposal to Congress to unify multi-layered police forces in Mexico's 31 states. (Photo by Daniel Becerril/Reuters)

A British policewoman chasing after a group of naked street boys by the Serpentine in Hyde Park, London. (Photo by Reg Speller/Getty Images). 1926

Michael Bath, from McLeans Ridges in New South Wales, Australia, estimates that in his lifetime he has taken more than 3,500 images of lightning bolts illuminating the sky. Photo: Alstonville, New South Wales, Australia – January 8, 2003. (Photo by Michael Bath/Caters News)

Japanese macaque monkeys enjoy sitting in the hot springs at Jigokudani-Onsen (Hell Valley) on January 23, 2005 in Jigokudani, Nagano-Prefecture, Japan. Japanese Macaques, also known as snow monkeys are the most northerly nonhuman primate in the world. In 1963 a female Macaque ventured into the hot springs to retrieve some soybeans. This behaviour was adopted by other monkeys, and eventually by the entire troop. This Macaque troop regularly visits the Jigokudani-Onsen springs to escape the cold. The hot springs are said to help relieve nerve pain and fatigue. (Photo by Koichi Kamoshida/Getty Images)

A protester uses molotov cocktails against riot police during May Day protests on May 1, 2010 in Athens, Greece. (Photo by Milos Bicanski /Getty Images)

Riot police walk in the street as a couple kiss on June 15, 2011 in Vancouver, Canada. Vancouver broke out in riots after their hockey team the Vancouver Canucks lost in Game Seven of the Stanley Cup Finals. (Photo by Rich Lam/Getty Images)

Police academy graduates march during their graduation ceremony in Islamabad, Pakistan May 18, 2015. Out of the 408 graduating officers, 76 female officers were inducted into the Pakistan police force, according to the police force. (Photo by Caren Firouz/Reuters)

Japanese macaques are relaxed in an outdoor hot spring bath at Hakodate Tropical Botanical Garden on December 1, 2016 in Hakodate, Hokkaido, Japan. The garden offers the hot spring treatment to macaques until May next year. (Photo by The Asahi Shimbun via Getty Images)