Passengers travel on the London train and underground system during the Christmas party season, December 18, 2015. (Photo by Paul Hackett/Reuters)

Policewomen take a picture inside a tunnel under the Chao Phraya river at a Mass Rapid Transit subway station in Bangkok, Thailand, December 14, 2015. (Photo by Athit Perawongmetha/Reuters)

A four-year-old dog Nika stands next to an image of Cuba's revolutionary hero Ernesto “Che” Guevara in front of a flooded street in Havana, January 23, 2016. Havana's seafront Malecon continued to be slammed by massive waves that flooded parts of the seaside city on Saturday. As a result, Havana was confronting flooding as a cold front passes through the Caribbean island. The giant waves began washing up onto shore during sunrise. The waves have been accompanied by winds passing through at a speed between 35 and 50 km (21 to 31 miles) per hour. (Photo by Alexandre Meneghini/Reuters)

Pakistani street performers sit around fire waiting for customers on a chilly evening in Rawalpindi, Pakistan, Wednesday, February 10, 2016. (Photo by B.K. Bangash/AP Photo)

Soldiers from Japan's Ground Self Defense Force come ashore in amphibious assault vehicle as they train alongside U.S. Marines during the bilateral annual Iron Fist military training exercise in Camp Pendleton, California February 26, 2016. (Photo by Mike Blake/Reuters)

A Syrian boy is comforted as he cries next to the body of a relative who died in a reported airstrike on April 27, 2016 in the rebel-held neighbourhood of al-Soukour in the northern city of Aleppo. The Syrian army was preparing an offensive to retake the whole of Aleppo, as fighting in the divided second city killed 38 civilians in a new blow for a tattered truce. Nearly 200 people have been killed in Aleppo in the past week as rebels have pounded government-held neighbourhoods with rocket and artillery fire and the regime has hit rebel areas with air raids. (Photo by Karam Al-Masri/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)

Smoke rises from a house days after part of the ground it was resting on collapsed into Lake Whitney, Texas in this June 13, 2014 file photo. I was covering the controlled burn of a house slowly falling into Lake Whitney due to the decaying cliff underneath. Asked to take photos from an aerial perspective, an instructor and I took off from Grand Prairie Municipal Airport around 9am. The burn, scheduled to start an hour later, was delayed. I love flying, but patience proved challenging as circling for nearly three hours gets boring fast. Once the fire started we only had 15 minutes to take photos because the plane was booked at 1pm. The owners invested their retirement savings in the house and were even advised by geologists that the ground was stable. To watch your investment literally go up in flames must take its toll emotionally. The owners said they don't expect their insurance to cover the loss. (Photo and caption by Brandon Wade/Reuters)