Russian police detain a protester at a demonstration against President Vladimir Putin in St.Petersburg, Russia, Saturday, May 5, 2018. (Photo by Dmitri Lovetsky/AP Photo)

In this photo taken Wednesday, November 26, 2014 attack dogs and their handlers apprehend a “rhino poacher” center, after alighting from a helicopter into water, in a simulation exercise showing training at an academy run by the Paramount Group, near Rustenburg, South Africa. The course prepares canine units to find firearms or contraband, track suspects in the undergrowth and abseil in harnesses from helicopters in pursuit of poachers. Dogs and handlers learn to trust each other and fine tune a relationship balancing control and aggression. (Photo by Denis Farrell/AP Photo)

Sydneysiders walk amongst tar figures placed in the CBD to raise awareness about the damage smoking causes to the body at Martin Place on June 30, 2011 in Sydney, Australia. Each of the tar figures represent the profile of smokers, from the casual weekend smoker to the one with a lifelong addiction. (Photo by Lisa Maree Williams/Getty Images)

A South Korean soldier wear North Korea's military uniform, acting as North Korean soldier during an anti-terror and anti-chemical drill session held as part of the 2011 Ulchi Freedom Guardian (UFG) event on August 17, 2011 in Seoul, South Korea. The 11-day UGC, which features drills including the handling of chemical and biological attacks, is a regular joint exercise between US and South Korean troops to prepare for potential emergencies on the Korean Peninsula. (Photo by Chung Sung-Jun/Getty Images)

Russian oppostion activists take part in a rally and march to Bolotnaya Square on February 4, 2012 in Moscow, Russia. Demonstrators braved temperatures as low as -20 degrees celsius as they took to the streets exactly one month before the presidential elections in protest against Vladimir Putin's efforts to return to the Kremlin for an unprecedented third term as President. (Photo by: Ilya Varlamov; Source: LiveJournal)

A Brazilian Navy member ejects spent cartridges while shooting rubber bullets during an exhibition of their operational capacity to combat terrorist attacks and riots ahead of the FIFA Confederations Cup and World Youth Day in Rio de Janeiro on May 27, 2013. (Photo by Ricardo Moraes/Reuters)

Participants of an unauthorized opposition rally gather in Tverskaya street in central Moscow on June 12, 2017. Authorities detained Russian opposition politician Alexei Navalny and hundreds of his supporters on Monday, as they mounted demonstrations across the nation against government corruption. Over 200 were detained in Moscow and Saint Petersburg an hour into the protest, according to an NGO that tracks arrests, with Navalny himself picked up by police in his building as he was headed to the event. (Photo by Vasily Maximov/AFP Photo)