Girls sit inside an empty classroom as they pose for a photograph during a celebration marking the end of the school year in the town of Douma, eastern Ghouta in Damascus, Syria May 21, 2016. (Photo by Bassam Khabieh/Reuters)

A woman mourns the loss of her husband, next to a placard which reads “I'm a pusher”, who was shot dead by an unidentified gunman in Manila on July 23, 2016. Philippine President Rodrigo Duterte swept to power in May on a promise to clampdown on drugs, and police have since confirmed killing nearly 200 people in a two-month crime blitz. There has also been a surge in killings by anti-drug vigilantes who leave victims' corpses on city streets wrapped in packaging tape with signs accusing them of being drug dealers. (Photo by Noel Celis/AFP Photo)

A Sadhu or a Hindu holy man offers prayers while sitting inside a circle of burning “Upale” (or dried cow dung cakes) on the occasion to mark the Basant or spring festival, on the banks of river Ganga in the northern Indian city of Allahabad January 24, 2015. Basant is celebrated mainly in the northern Indian states marking the start of the spring season. (Photo by Jitendra Prakash/Reuters)

Chinese Kazakh eagle hunters sit on horseback as they travel to a local competition on January 29, 2015 in the mountains of Qinghe County, Xinjiang, northwestern China. The festival, organised by the local hunting community, is part of an effort to promote and grow traditional hunting practices for new generations in the mountainous region of western China that borders Kazakhstan, Russia and Mongolia. The training and handling of the large birds of prey follows a strict set of ancient rules that Kazakh eagle hunters are preserving for future generations. (Photo by Kevin Frayer/Getty Images)

A flight deck crew prepares to launch a F18 Super Hornet from the deck of the USS Eisenhower off the coast of Virginia, December 10, 2015 in the Atlantic Ocean. US Defense Secretary Ash Carter visited the carrier with India's Minister of Defense Manohar Parrikar to demonstrate US Navy aircraft carrier flight operations. (Photo by Mark Wilson/Getty Images)

A man and a girl take a dip in icy waters during celebrations for the Orthodox Epiphany in the Sea of Japan in the far eastern city of Vladivostok, Russia, January 19, 2016. Orthodox believers mark Epiphany on January 19 by immersing themselves in icy waters regardless of the weather. (Photo by Yuri Maltsev/Reuters)

Indian dancers perform a fire breathing act during a procession to mark the 661st anniversary of the birth of Hindu guru Bawa Lal Dayal Maharaj in Amritsar on February 9, 2016. Bawa Lal Dayal Maharaj, a popular leader of his time, is especially revered by devotees of a temple in the town of Dhyanpur, some 45 kms north of Amritsar. (Photo by Narinder Nanu/AFP Photo)

Labourers pour molten iron into a container at a foundry in Xiangfan, Hubei province in this July 2, 2010 file photo. Iron ore is enjoying its biggest rally in years, outpacing copper and oil so far in 2016, but still weak forward prices show it may be tough to stretch the bullish outlook. Improving steel prices in top market China are helping fuel iron ore's climb as producers gear up for a seasonal uptick in demand. Yet there is no shortage of doubters who see gains in the bulk commodity as fleeting given a large glut and challenges for China's economy. (Photo by Reuters/Stringer)