A rebel fighter carries his weapon as he moves through a hole in a wall in the old city of Aleppo near the frontline against forces loyal to Syria's President Bashar al-Assad December 28, 2014. (Photo by Jalal Al-Mamo/Reuters)

A man covered with dust sits on a street following a reported air strike by Syrian government forces in the rebel-held neighbourhood of Sukkari in the northern city of Aleppo on May 30, 2016. (Photo by Baraa Al-Halabi/AFP Photo)

This Wednesday, August 31, 2016 photo, provided by the Syrian anti-government activist group Aleppo Media Center (AMC), shows Syrian boys dive into a hole filled with water that was caused by a missile attack in the rebel-held neighborhood of Sheikh Saeed in Aleppo province, Syria. (Photo by Aleppo Media Center via AP Photo)

A man reacts over dead bodies prior to burial in a graveyard after shelling in the rebel held besieged town of Douma, eastern Ghouta in Damascus, Syria, October 24, 2016. (Photo by Bassam Khabieh/Reuters)

Internally displaced Syrian children who fled Raqqa city stand near their tent in Ras al-Ain province, Syria January 22, 2017. (Photo by Rodi Said/Reuters)

The Borobudur temple seen illuminated during Vesak Day, commonly known as “Buddha's birthday”, at the Borobudur Mahayana Buddhist monument on May 6, 2012 in Magelang, Indonesia. Buddhists in Indonesia celebrate Vesak at the Borobudur temple annually, which makes it the most visited tourist attraction in Indonesia. Vesak is observed during the full moon in May or June and the ceremony centers around three Buddhist temples, whereby pilgrims walk from Mendut to Pawon, ending at Borobudur. The stages of life of Buddhism's founder, Gautama Buddha, which are celebrated at Vesak are his birth, enlightenment to Nirvana, and his passing. (Photo by Ulet Ifansasti/Getty Images)

A scantily-clad brunette is pictured passed out on the pavement. Mayhem hits the streets of Newcastle, UK as clubbers out on the Toon have a little too much to drink as they enjoy the Bank Holiday on August 29, 2016. Photographs take last night show scantily-clad women passed out on the pavement, while boozed-up men were caught arguing with police. (Photo by XposurePhotos.com)

A man carries an injured woman in a site hit by what activists said were airstrikes carried out by the Russian air force in the rebel-controlled area of Maaret al-Numan town in Idlib province, Syria January 9, 2016. At least 70 people died in what activists said where four vacuum bombs dropped by the Russian air force in the town of Maaret al-Numan; other air strikes where also carried out in the towns of Saraqib, Khan Sheikhoun and Maar Dabseh, in Idlib. (Photo by Khalil Ashawi/Reuters)