A dog swims as a resident navigates his boat in a neighbourhood flooded by the Purus river, which continues to rise from days of heavy rainfall in the region, in Boca do Acre, Amazonas state March 14, 2015. According the state civil defense, more than 20,000 people have been left homeless along the Purus river, where incessant rains have flooded the area and caused the river to burst their banks. (Photo by Bruno Kelly/Reuters)

Al-Shamiyah Front fighters inspect a new locally-made cannon named “Borkan” (Volcano) as it was being launched towards forces loyal to Syria's president Bashar Al-Assad located in Aleppo artillery school, March 7, 2015. The “Borkan” is made out of four tubes attached to a loader, which can fire four shells at a time, and have a range of three kilometers (1.86 miles). (Photo by Abdalrhman Ismail/Reuters)

Pedestrians and workers pass an upside down car art installation in a car park on the South Bank in London, February 19, 2015. British artist Alex Chinneck's illusory piece, entitled “Pick yourself up and pull yourself together”, and on display in the working car park for a week, sees a Vauxhall car suspended upside down, appearing to be gripping onto a peeled back length of tarmac. (Photo by Toby Melville/Reuters)

A member from the Iraqi security forces beats an Islamic State insurgent, who was captured in Tikrit April 1, 2015. Iraqi troops and Shi'ite paramilitary fighters were battling Islamic State on Wednesday in northern Tikrit, which officials described as the Sunni Muslim militant group's last stronghold in the city. (Photo by Alaa Al-Marjani/Reuters)

Couples (L-R) Chaiyut Phuangphoeksuk and Prontathourn Pronnapatthun, and Nichapatr Koomsombut and Pirat Rungthongoran run from sheep during their wedding ceremony at a resort in Ratchaburi province February 13, 2015. Three Thai couples took part in the wedding ceremony arranged by a resort themed around fun activities ahead of Valentine's Day. (Photo by Athit Perawongmetha/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)

Birds fly over the Atomic Bomb Dome in Hiroshima, western Japan July 29, 2015. On August 6, 1945, the U.S. dropped the atomic bomb on Hiroshima, killing about 140,000 by the end of the year in a city of 350,000 residents, in the world's first nuclear attack. Three days later, a second atomic bomb was dropped on Nagasaki. Influenced by the shadows scorched into outdoor surfaces by the heat of the blasts 70 years ago, Reuters photographer Issei Kato pays homage to survivors, residents and historic buildings in both cities in a personal project that captures the shadows of today. (Photo by Issei Kato/Reuters)

Damaged train coaches at the site of a train accident, 180 kilometers from Bhopal near Harda district of Mahdya Pradesh, India, 05 August 2015. At least 25 people died when two passenger trains derailed in central India after heavy monsoon rains flooded railway tracks, officials said. Ten coaches from the trains toppled while approaching a small bridge just before midnight. (Photo by Sanjeev Gupta/EPA)