A member of the Community Police of the FUSDEG (United Front for the Security and Development of the State of Guerrero) poses with a weapon during events to mark the first anniversary of the force's operations in Ocotito, January 23, 2015. Based on the traditional indigenous justice system, the Community Police is made up of volunteers from different communities of Guerrero, and was created in response to the spate of violence in several locations in the state. (Photo by Jorge Dan Lopez/Reuters)

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)

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)

South Korean teenagers participate in a warfare exercise as part of the Special Warfare Command's training course at a military base on August 4, 2011 in Seoul, South Korea. About 1,000 civilian volunteers including middle and high school students participated in the special force's four-day training programme to develop their spiritual and physical strength. (Photo by Chung Sung-Jun/Getty Images)

South Korea's Amry Special Warfare Command (SWC) soldiers aim their machine guns in a frozen river during a winter exercise in Pyeongchang, South Korea, Thursday, January 8, 2015. About 200 SWC soldiers participated in this routine two-week winter drill. (Photo by Ahn Young-joon/AP Photo)

A member of a female grappling team from Qinghai Province armed police undergoes dagger exercise on August 8, 2006 in Xining of Qinghai Province, China. The female grappling team, established in May 2006, has 40 women soldiers aged 18 to 21. The training program includes grappling, boxing, dagger exercise and shooting. (Photo by China Photos). P.S. All pictures are presented in high resolution.

Egyptian riot police charge towards protesters near Egypt's Interior Ministry, as violent demonstrations continued into their second day on February 3, 2012 in central Cairo, Egypt. (Photo by Ed Giles/Getty Images)