Riot police officers in position to crack down on demonstrators during a protest against Venezuelan President Nicolas Maduro, in Caracas on April 20, 2017. Venezuelan riot police fired tear gas Thursday at groups of protesters seeking to oust President Nicolas Maduro, who have vowed new mass marches after a day of deadly unrest. Police in western Caracas broke up scores of opposition protesters trying to join a larger march, though there was no immediate repeat of Wednesday's violent clashes, which left three people dead. (Photo by Juan Barreto/AFP Photo)

The anthropometric record card of Sarah Giles, a servant who was convicted of stealing in 1897, on display making up part of a mosaic of cards on a table top during a press preview for the Crime Museum Uncovered exhibition at the Museum of London in the City of London, Wednesday, October 7, 2015. Drawn from Scotland Yard's private collection, the show charts more than a century of violence and suffering, from the murders of Jack the Ripper to IRA and al-Qaida bombings. But it also celebrates the brains, bravery and scientific advances that helped catch perpetrators and solve crimes. (Photo by Alastair Grant/AP Photo)

An area of vegetation can be seen amongst drought effected farmland in South Australia, November 12, 2015. A pioneering Australian scheme to improve the management of water in the world's driest inhabited continent is facing its first real test as an intensifying El Nino threatens crops and builds tensions between farmers and environmentalists. An El Nino, a warming of sea-surface temperatures in the Pacific, is already causing drought and other extreme weather, affecting millions of people across parts of the world, and experts warn that the intensifying weather pattern could emerge as one of the strongest on record. (Photo by David Gray/Reuters)

Chinese artist Kong Ning walks in her costume made of hundreds of orange plastic blowing horns during her art performance raising awareness of the hazardous smog in front of the Drum tower in a historical part of Beijing on a very polluted day December 7, 2015. Kong, whose works include themes related to China's air pollution problem, named her new performance “The Orange Horns Bride Marries the Blue Sky” and presented it dressed in orange, the colour of the second highest pollution alert level issued again in Beijing as hazardous smog blankets the capital. (Photo by Damir Sagolj/Reuters)

Chinese artist Kong Ning poses in a costume symbolizing a butterfly, which is decorated with 365 masks on its wings to represent the number of days in a year, during her performance art at the Badaling section of the Great Wall on the outskirts of Beijing January 1, 2015. Kong, whose works include themes related to China's air pollution problem, named her new performance art “Hua Die” (transforming into a butterfly) and performed it on the first day of the new year as she hopes that China has clean air for this year. (Photo by Kim Kyung-Hoon/Reuters)

Alex “Torreto” Vellios, a 26-year old barber sports his tattoo of an open razor as he holds a real razor while preparing for his first customer of the day at his Torreto barber shop in Frankfurt, January 6, 2015. Inspired by a childhood trip to the barbers with his grandfather in Greece, Vellios, a formally trained hairdresser and self-taught barber, fulfilled his dream of opening his own gentleman's barber shop five months ago and has turned it into a successful male grooming and shaving business with customers now waiting up to three to four weeks for an appointment to see him. (Photo by Kai Pfaffenbach/Reuters)

A volunteer pets a tiger inside a cage at the Wat Pa Luang Ta Bua, otherwise known as Tiger Temple, in Kanchanaburi province February 12, 2015. Thai officials last week raided the Buddhist temple that is home to more than 100 tigers and are currently conducting an investigation into suspected links to wildlife trafficking. Authorities from Thailand's Department of National Parks, Wildlife and Plant Conservation on Thursday checked 143 Bengal tigers living at the temple, and found them to be in good health. (Photo by Athit Perawongmetha/Reuters)

An Olympic Airways airplane stands on the premises of the former Athens International airport, Hellenikon June 16, 2014. For about six decades Hellenikon was Athens' only airport but it closed down in 2001 to make way for a newer, more modern airport before the city hosted the 2004 Olympic Games. After languishing for years as a wasteland of crumbling terminals, Hellenikon is set for resurrection as a glitzy coastal resort. Lamda Development, controlled by Greece's powerful Latsis family and leading a consortium of Chinese and Abu-Dhabi based companies, has big dreams for the area since signing a 915 million euro deal for a 99-year lease in March 2014. (Photo by Yorgos Karahalis/Reuters)