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)

A Syrian boy is comforted as he cries next to the body of a relative who died in a reported airstrike on April 27, 2016 in the rebel-held neighbourhood of al-Soukour in the northern city of Aleppo. The Syrian army was preparing an offensive to retake the whole of Aleppo, as fighting in the divided second city killed 38 civilians in a new blow for a tattered truce. Nearly 200 people have been killed in Aleppo in the past week as rebels have pounded government-held neighbourhoods with rocket and artillery fire and the regime has hit rebel areas with air raids. (Photo by Karam Al-Masri/AFP Photo)

Syrian civil defence volunteers, known as the White Helmets, rescue a boy from the rubble following a reported barrel bomb attack on the Bab al- Nairab neighbourhood of the northern Syrian city of Aleppo on November 24, 2016. (Photo by Ameer Alhalbi/AFP Photo)

Charlotte Caslick of Australia is tackled by Jasmine Joyce of Wales during the Rugby Sevens Women's Pool B match between Australia and Wales on day nine of the Gold Coast 2018 Commonwealth Games at Robina Stadium on April 13, 2018 on the Gold Coast, Australia. (Photo by Dan Mullan/Getty Images)

Elizabeth Mills jumps in front of the Conservative Political Action Conference (CPAC) sign at National Harbor, Md., February 23, 2018. (Photo by Joshua Roberts/Reuters)

A young girl takes selfie with Easter rabbit sculpture during the Easter eggs (Pysanka) and rabbit exhibition in front of St. Sophia Cathedral in Kiev, Ukraine, 05 April 2018. Ukrainians will mark Orthodox Easter on 08 April 2018, according to Julian calendar. (Photo by Sergey Dolzhenko/EPA/EFE/Rex Features/Shutterstock)

A drunk student is sick on the street watched by a police officer following a night of heavy drinking during freshers week in United Kingdom on November 28, 2007. (Photo by Matthew Horwood/Alamy Stock Photo)

A burning tank is in Daraa, on March 9, 2013. (Photo by Ali Abu-Salah/Reuters/Shaam News Network via The Atlantic)