Actors perform a scene in a film directed by Humam Husari in the rebel-held besieged town of Zamalka, in the Damascus suburbs, Syria September 19, 2016. (Photo by Bassam Khabieh/Reuters)

A Swiss police officer accompanies a migrant from Syria carrying her baby, upon her arrival at the railway station in the north-eastern Swiss town of Buchs September 1, 2015. (Photo by Arnd Wiegmann/Reuters)

An Israeli tank moves into position in the Israeli controlled Golan Heights during fighting between forces loyal to Syrian President Bashar Assad and rebels in the Druze village of Khader in Syria, Tuesday, June 16, 2015. As many as 20 members of the Druze minority sect were killed last week, the deadliest violence against the Druze since Syria's conflict started in March 2011, sparking fears of a massacre against the sect. (AP Photo/Ariel Schalit)

Syrian fighters from the Turkish-backed National Liberation Front (NLF) fire a missile against regime positions on May 13, 2019 in the rebel-held northern part of Syria's Hama province. Clashes on the edge of a jihadist bastion in northwestern Syria have killed at least 42 fighters in 24 hours, a monitor said today, after regime bombardment on the region devastated health services. (Photo by Omar Haj Kadour/AFP Photo)

A Kurdish female fighter from the People's Protection Units (YPG) gestures as she carries her weapon near al-Hawl area where fighting between Islamic State fighters and fighters from Democratic Forces of Syria are taking place in south-eastern city of Hasaka, Syria November 10, 2015. (Photo by Rodi Said/Reuters)

A combination picture shows Aleppo's Umayyad mosque, Syria, before it was damaged on March 12, 2009 (top) and after it was damaged (bottom) December 13, 2016. (Photo by Omar Sanadiki/Reuters)

A girl pours water over a dog to cool it down, in the rebel held besieged town of Douma, eastern Damascus suburb of Ghouta, Syria, June 23, 2016. (Photo by Bassam Khabieh/Reuters)

A Kurdish fighter from the People's Protection Units (YPG) fires his rifle at Islamic State militants as he runs across a street in Raqqa, Syria, July 2017. (Photo by Goran Tomasevic/Reuters)