Smoke and dust billows after an explosion in the embattled northern Syrian city of Raqqa on September 3, 2017. #

A Syrian woman looks back as civilians gather on the western front after fleeing the center of Raqqa on October 12, 2017. #

Destruction in a street in the former ISIS stronghold of Raqqa on September 22, 2017. #

Members of the Syrian Democratic Forces drive towards the eastern front line of Raqqa on September 24, 2017. #

A member of the Syrian Democratic Forces runs to take cover from sniper shots near the central hospital of Raqqa on October 1, 2017. #

A member of the SDF checks a building near the central hospital of Raqqa on October 1, 2017. #

An unexploded car bomb sits idle on the western front line of Raqqa after its driver was shot by members of the SDF on October 8, 2017. #

A booby trap is pictured in a stairwell near a position of the SDF near the stadium in Raqqa on October 4, 2017. #

A member of the SDF monitors the area on the western front line in Raqqa on October 8, 2017. #

An injured member of the SDF holds his walkie-talkie as he hides from an ISIS sniper in the Old City of Raqqa on August 19, 2017. #

A member of the SDF calls his comrades during the fighting with ISIS in Raqqa on August 14, 2017. #

Smoke and dust rise above positions of ISIS militants after an airstrike by coalition forces near the stadium in Raqqa on October 4, 2017. #

A member of the SDF comforts his wounded comrade Ibrahim after the latter was shot by a sniper on the eastern front line of Raqqa on September 24, 2017. #

A fighter from the SDF takes a selfie as he stands near rubble at a damaged site in Raqqa on September 25, 2017. #

A U.S. military convoy drives on a highway from Kobane to Ain Issa, north of Raqqa, Syria, on September 29, 2017. #

A woman stands outside a tent at a camp for people displaced from fighting in Raqqa, in Ain Issa, Syria, on June 14, 2017. #

Members of the Women's Protection Units (YPJ) arrive on the front line on the eastern outskirts of Raqqa on July 18, 2017, during the ongoing offensive by the SDF. #

A teenager holds a cooker at a camp for people displaced from fighting in Raqqa, in Ain Issa, on June 14, 2017. #

A displaced Syrian girl from Raqqa in a refugee camp in Ain Issa on September 23, 2017. #

Syrians displaced from the city of Deir Ezzor gather on the outskirts of Raqqa on October 2, 2017. #

A female member of the SDF holds a position inside a building in an area close to the Old City in the embattled northern Syrian city of Raqqa on September 3, 2017. #

Children attend their first class immediately after they registered at the school in Hazema, North Raqqa, on August 21, 2017. #

Buildings destroyed by fighting between Syrian Democratic Forces and ISIS militants in Raqqa's Old City on October 5, 2017. #

A member of the SDF looks out of a hole to check an area on the eastern front line in the old city center of Raqqa on September 25, 2017. #

Members of the SDF control their drone at an advance position during the fighting with ISIS fighters in Nazlat Shahada, a district of Raqqa, on August 16, 2017. #

A picture taken on September 5, 2017, shows smoke and dust billowing following a coalition airstrike in the western al-Daraiya neighborhood of Raqqa. #

A member of the SDF keeps watch as he sits in front of ISIS positions in Raqqa, Syria, on August 14, 2017. #

Members of the SDF are seen inside a Hummer during a battle against ISIS jihadists to retake the central hospital of Raqqa on September 28, 2017. #

Kurdish fighters from the People's Protection Units (YPG) fire at a drone operated by ISIS militants in Raqqa on June 16, 2017. #

War-damaged buildings in the Old City of Raqqa, Syria, on August 19, 2017. #