Indigenous Sahrawi girls play on an improvised see-saw at a refugee camp of Boudjdour in Tindouf, southern Algeria March 3, 2016. UN Secretary General Ban Ki-moon is scheduled to visit the Sahrawi refugees in south-west Algeria's Tindouf region. (Photo by Zohra Bensemra/Reuters)

A man carries an injured girl after what activists said were five air strikes by forces loyal to Syria's President Bashar al-Assad in Douma, eastern al-Ghouta, near Damascus September 11, 2014. (Photo by Bassam Khabieh/Reuters)

Filipino children play as they are doing caroling activities on the street near an airport, days before Christmas in Manila, Philippines, 20 December 2017. Filipinos celebrate the longest Christmas in the world which starts as early as September every year. (Photo by Francis R. Malasig/EPA/EFE)

A picture made available 26 April 2016 shows a tiger playing in the water with a trainer nicknamed “Super Tiger Man” at the Tiger Temple in Kanchanaburi province, Thailand, 24 April 2016. The site known in Thai as “Wat Pa Luangta Maha Bua Yannasampanno” has been the focus of a dispute with the Department of National Parks, Wildlife and Plant Conservation (DNP) after the DNP asked in 2015 that the temple hands over its 147 tigers since it was not licensed to keep them. The temple has requested for a zoo license according to its managing director. (Photo by Diego Azubel/EPA)

A Muslim boy takes part in Friday prayers on a street outside a mosque in Mumbai, India, June 24, 2016. (Photo by Shailesh Andrade/Reuters)

Chinese relative of a missing passenger on Malaysia Airlines flight MH370 reacts as she weeps outside the main gate of the Lama Temple on March 8, 2015 in Beijing, China. Foreign and local media were prevented by Chinese police from covering the relatives visit to the temple where they tried to pray .There were 239 people on board the flight when it disappeared March 8, 2014 en route from Kuala Lumpur to Beijing. After one year and an exhaustive search, investigators still have no clue as to the whereabouts of the missing airliner. (Kevin Frayer/Getty Images)

Ammunition airlift into besieged Khe Sanh, Operation Pegasus, April 1968. (Photo by Larry Burrows/AP Photo)

American soldiers leaping from an armoured personnel carrier during exercises in Korea, 17th March 1954. (Photo by Three Lions)