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)

Filipino typhoon survivor children, who escaped after their village was attacked by allegedly armed men, wait for social workers in the super typhoon devastated city of Tacloban, Leyte province, Philippines, 13 November 2013. Aid workers and relief supplies were being poured into eastern provinces hit by Typhoon Haiyan, which aid agencies and officials estimated has left thousands dead and staggering destruction in its wake. The official death toll in the Philippines from one of the world’s strongest typhoons rose to 1,833, the national disaster relief agency said with many towns still unaccounted for. (Photo by Dennis M. Sabangan/EPA)

Syrian refugee girl Nur El-Huda, 9, shows a drawing of her home in Syria, in her classroom in Yayladagi refugee camp in Hatay province near the Turkish-Syrian border, Turkey, December 16, 2015. Syria's conflict has left hundreds of thousands dead, pushed millions more into exile, and had a profound effect on children who lost their homes or got caught up in the bloodletting. The drawings of young refugees living in Turkey show their memories of home and hopes for its future. The pictures also point to the mental scars borne by 2.3 million Syrian refugees living in Turkey, more than half of them children. (Photo by Umit Bektas/Reuters)

Police officers control the crowd (rear) while surrounding a man (front C) suspected to be involved in opening fire on a beachside hotel in Sousse, Tunisia, as a woman reacts (R), June 26, 2015. At least 27 people, including foreign tourists, were killed when at least one gunman opened fire on a Tunisian beachside hotel in the popular resort of Sousse on Friday, an interior ministry spokesman said. Police were still clearing the area around the Imperial Marhaba hotel and the body of one gunman lay at the scene with a Kalashnikov assault rifle after he was shot in an exchange of gunfire, a security source at the scene said. (Photo by Amine Ben Aziza/Reuters)

Cycling jerseys, part of a collection belonging to French cycling fan Gerald, hang from a line during the 4th stage of the Tour de France cycling race from Seraing in Belgium to Cambrai in France, July 7, 2015. Photographing the Tour de France cycling race comes with highs and lows: the buzz from capturing just the right image, the tedium of long journeys, the painstaking set-up of equipment, the breath-taking scenery. Reuters photographers have worked not only to capture the thrills and spills on the roads and mountain passes. They have also shot a set of pictures showing their own quirky view from behind the scenes as they travelled through the Netherlands, Belgium and France. (Photo by Eric Gaillard/Reuters)

Starting in September, Indonesia's Mount Sinabung began erupting yet again. In the days that followed, ash and smoke were shot into the air multiple times. As a result, nearby towns turned gray from repeated blows by the volcano. Photo: A man uses his mobile phone as Mount Sinabung continues to erupt, with hot smoke spewing from the volcano, in the Karo district on the north of Indonesia's Sumatra island on November 18, 2013. Officials said a week ago at more than 5,000 people had fled their homes since the volcano erupted early this month. (Photo by Sutanta Aditya/AFP Photo)

The galactic core of the milky way occupied by two small wooden boats on July 2, 2014, in Isle of Wight, UK. The Milky Way shines in mesmerizing colourful patterns above the Isle of Wight in stunning photographs. Chad Powell used a DSLR camera to capture images of the spectacular constellation above the familiar beach scenes of England's largest island. The 22-year-old, who shot the pictures over a year of stargazing on the island, often stayed up until dawn to catch the most dramatic sky-scapes. Chad, a graphic designer from Ventnor, Isle of Wight, used foregrounds of abandoned theme parks, harbors and lighthouses against the illuminated sky. Minor adjustments were made to bring out the contrast and whites in the images. (Photo by Chad Powell/Barcroft Media)

Two rainbows emerge from a black storm above the mountains, on August 19, 2014, in Kingman, Arizona. Double tornadoes, lightning storms and rotating supercells – this is what it's like to chase storms for a year. These dramatic images show apocalyptic weather throughout 2014 from a lightning storm to a pair of rainbows. Roger Hill, 57, has been chasing storms in the United States for thirty years and runs a tour operation with his wife Caryn. His favourite photograph of the year was also one of the most difficult to get – as two violent tornadoes tore through Pilger, Nebraska on June 16. The spiraling winds killed a five-year-old girl and injured at least 19 others, and as Roger tried to get the perfect shot debris began to rain down on his car. (Photo by Roger Hill/Barcroft Media)