A man is seen trapped amid the debris of an under-construction flyover after it collapsed in Kolkata, India, March 31, 2016. Using saws, small cranes and bare hands, rescuers on Friday cleared the crumbled concrete and twisted steel from an overpass that collapsed onto a crowded Kolkata neighborhood, killing at least 23 people and injuring more than 80. With more than half the debris cleared by Friday morning, 67 people have been pulled out alive, police said. (Photo by Rupak De Chowdhuri/Reuters)

Pedestrians and vehicles make their way past the Potala Palace early on a rainy morning in Lhasa, capital of the Tibet Autonomous Region in China, Saturday, September 19, 2015. Chinese officials have taken foreign journalists on a visit to the region, normally off-limits to them, weeks after Communist Party officials commemorated the 50th anniversary of the establishment of the Tibet Autonomous Region. (Photo by Aritz Parra/AP Photo)

The "Skylanders Eruptor" balloon moves by people on balconies during the 89th Macy's Thanksgiving Day Parade in the Manhattan borough of New York, November 26, 2015. (Photo by Andrew Kelly/Reuters)

Young girls dress up in traditional costumes and pose for a selfie at the opening ceremony of the Leishan Miao new year festival in the city of Kaili, Guizhou province, China on November 23, 2015. (Photo by Imaginechina/Rex Shutterstock)

A rusty revolver is seen near the body of a man, who police said was killed by police operatives, and two sachets of “Shabu” or methampethamine chloride were found on his pockets in Manila, Philippines August 17, 2017. (Photo by Erik De Castro/Reuters)

A passenger plane, with a full Harvest moon seen behind, makes its final landing approach towards Heathrow Airport in London, Britain, October 5, 2017. (Photo by Toby Melville/Reuters)

The annual calendar features stunning shots of lighting, cloud formations and the aurora australis. Hundreds of photographers from every Australian state and territory submitted images to the Bureau of Meteorology for selection in the year’s calendar, with only the best chosen to represent the full spectrum of Australian weather. Here: April. A path through the clouds between Townsville and Richmond, Queensland. (Photo by Captain Victoria Harrison/Australian Bureau of Meteorology)

Clouds gather as walkers pause atop a ridge in Mountain View, California January 7, 2016. (Photo by Noah Berger/Reuters)