Medics carry a wounded person at the scene after an attack at a popular nightclub in Istanbul, early Sunday, January 1, 2017. Istanbul Governor Vasip Sahin said that an armed assailant has opened fire at a nightclub in Istanbul during New Year's celebrations. Turkish authorities have banned distribution of images relating to the Istanbul attack within Turkey. (Photo by IHA via AP Photo)

In this May 14, 2016 photo, children wearing their school backpacks climb on a cliff using a bamboo ladder on their way home from school in Zhaojue county, southwest China's Sichuan province. A village in China's mountainous west where schoolchildren must climb an 800-meter (2,625-foot)-high bamboo ladder secured to a sheer cliff face may get a set of steel stairs to improve it's safety. (Photo by Chinatopix via AP Photo)

In this image provided by the Pairi Daiza park, giant panda Hao Hao holds her newborn baby in her mouth at the park in Brugelette, Belgium, on Thursday, June 2, 2016. With the help of the Chinese government Hao Hao and her mate Xing Hui arrived in Belgium two years ago and Pairi Daiza adapted its park to build a bamboo forest for them. (Photo by Benoit Bouchez/Pairi Daiza via AP Photo)

Residents carry an injured woman rescued from a collapsed house in Funing county in Yancheng city of eastern China's Jiangsu Province on Thursday June 23, 2016. A powerful tornado hit Thursday, with reports of dozens killed and large numbers of buildings destroyed in the eastern Chinese province of Jiangsu, according to state media. (Photo by Chinatopix via AP Photo)

Umbrellas are placed over the statute of the Beatles, during a photocall, on Liverpool's waterfront, in Liverpool, England, Wednesday, March 22, 2017. The city of Liverpool is getting set to celebrate the half-centenary of “Sgt. Pepper's Lonely Hearts Club Band”, one of the most influential albums by local heroes The Beatles. (Photo by Peter Byrne/PA Wire via AP Photo)

In this June 29, 2016 file photo, boats docked at Central Marine in Stuart, Fla., are surrounded by blue green algae. The 153-mile-long Indian River Lagoon has been plagued by harmful algae blooms. Water quality testing data analyzed by the AP showed the average phosphorous level – a byproduct of fertilizers and human waste that algae thrive on, rose nearly 75 percent between 2000 and 2016. (Photo by Greg Lovett/The Palm Beach Post via AP Photo)

U.S Army combat camera photographer Spc. Hilda Clayton took this photo July 2, 2013 that was released by the U.S. Army, that shows an Afghan soldier engulfed in flame as a mortar tube explodes during an Afghan National Army live-fire training exercise in Laghman Province, Afghanistan. The accident killed Clayton and four Afghan National Army soldiers. (Photo by Spc. Hilda Clayton/U.S. Army via AP Photo)

A woman plays around as she walks across a glass-bottomed suspension bridge in a scenic zone in Pingjiang county in southern China's Hunan province Thursday, September 24, 2015. The bridge, 300 meters (984 feet) long and 180 meters (590 feet), opened to visitors on Thursday for the first time since its conversion from a regular suspension bridge was completed. (Photo by Chinatopix Via AP Photo)