A mobile phone cover with a picture of Russian President Vladimir Putin and which reads “Mr President” is seen in this photo illustration taken a in hotel room in Kazan, Russia, July 30, 2015. He may be in charge of an economy in crisis, but if mobile phone covers and souvenir mugs are a barometer of popularity, Russian President Vladimir Putin need not fear for his political future. In fact, Moscow's annexation of Crimea from Ukraine last year has given the memorabilia makers even more material to glorify, sometimes wryly, a president whose image as a champion of Russian national interests in a hostile world is barely challenged in his own country. (Photo by Stefan Wermuth/Reuters)

Members of the Ukrainian Interior Ministry's special battalion Kiev-1 rescue a hostage, who was detained by a mock terroist, during an anti-terror drill in Kiev, Ukraine, August 28, 2015. (Photo by Valentyn Ogirenko/Reuters)

In this October 6, 1976 file photo a member of a Thai political faction strikes at the lifeless body of a hanged student outside Thammasat University in Bangkok October 6, 1976. For some Thais, the bloody events of October 6, 1976 are still a nightmare. On that day, heavily armed security forces shot up Bangkok's Thammasat University campus and killed scores of students, while right-wing vigilantes captured would-be escapees, subjecting them to ghoulish lynchings. (Photo by Neal Ulevich/AP Photo)

People sit on the top of a truck heavily piled with corn-stalks plies as they head for Mogadishu from Afgooye on October 19, 2016. At least four police officers were killed on October 18 when a suicide bomb attacker rammed an explosives-packed car into a police station before fighters from the Al-Qaeda-linked Shabaab group subsequently stormed the area killing at least 10 people, including soldiers and civilians. (Photo by Mohamed Abdiwahab/AFP Photo)

A hippopotamus is sprayed with water on a hot summer day at Anna National Zoological Park in Chennai, India on April 26, 2017. (Photo by Arun Sankar/AFP Photo)

Labourers break fast outside a shop in a market on the first day of the Muslim holy month of Ramadan in Karachi, Pakistan June 7, 2016. (Photo by Akhtar Soomro/Reuters)

MTV “Ex On The Beach” star Charlotte Dawson and Big Brother star Sam Giffen (not pictured) having fun on a night out in Manchester, England after leaving neighbourhood restaurant on September 8, 2016. (Photo by XposurePhotos.com)

Pablo Holcer tests out a VR system made by Neurable that allows the user to control with their thoughts as the EEG headset interprets thoughts into actions in the VR environment at SIGGRAPH 2017 in Los Angeles, California, July 31, 2017. (Photo by Mike Blake/Reuters)