Aleppo

A boy carries his belongings at a site hit by what activists said was a barrel bomb dropped by forces loyal to Syria's President Bashar al-Assad in Aleppo's al-Fardous district, Syria April 2, 2015. REUTERS/Rami Zayat/File Photo

Rami Zayat/Reuters

A boy carries his belongings at a site hit by what activists said was a barrel bomb dropped by forces loyal to Syria’s President Bashar al-Assad in Aleppo’s al-Fardous district, Syria

A Syrian man walks past destroyed buildings on May 2, 2016, in Aleppo's Bab al-Hadid neighbourhood which was targeted recently by regime air strikes.

Karam Al-Masri/AFP/Getty

A Syrian man walks past destroyed buildings in Aleppo’s Bab al-Hadid neighbourhood which was targeted recently by regime air strikes 

Syrians evacuate an injured man

AFP/Getty Images

Syrians evacuate an injured man amid the rubble of destroyed buildings following a reported air strike on the rebel-held neighbourhood of Al-Qatarji, in the northern Syrian city of Aleppo on Friday

Syrian civil defence volunteers and rescuers remove a baby from under the rubble of a destroyed building following a reported air strike on the rebel-held neighbourhood of al-Kalasa in the northern Syrian city of Aleppo.

Ameer Alhalbi/AFP/Getty Images

Syrian civil defence volunteers and rescuers remove a baby from under the rubble of a destroyed building following a reported air strike on the rebel-held neighbourhood of al-Kalasa in the northern Syrian city of Aleppo.

People inspect the damage at a site hit by airstrikes, in the rebel-held area of Aleppo's Bustan al-Qasr

Abdalrhman Ismail/Reuters

People inspect the damage at a site hit by airstrikes, in the rebel-held area of Aleppo’s Bustan al-Qasr, Syria on Thursday

Syrians help a wounded youth following a...Syrians help a wounded youth following an air strike on the Fardous rebel held neighbourhood of the northern Syrian city of Aleppo on April 26, 2016.  / AFP PHOTO / AMEER ALHALBIAMEER ALHALBI/AFP/Getty Images

Ameer Alhal/AFP/Getty

Syrians help a wounded youth following an air strike on the Fardous rebel held neighbourhood of the northern Syrian city of Aleppo

A Syrian man walks past damaged homes following a snow storm in the northern Syrian city of Aleppo on Tuesday. The conflict in Syria has killed more than 250,000 people and forced millions to flee their homes since it broke out in March 2011.

Karam Al-Masri/AFP

A Syrian man walks past damaged homes following a snow storm in the northern Syrian city of Aleppo on Tuesday

A Syrian man carries his two two girls as he walks across the rubble following a barrel bomb attack on the rebel-held neighbourhood of al-Kalasa in the northern Syrian city of Aleppo on Thursday. Once Syria's economic powerhouse, Aleppo has been ravaged by fighting since the rebels seized the east of the city in 2012, confining government forces to the west

Karam Al-Masri/AFP

A Syrian man carries his two two girls as he walks across the rubble following a barrel bomb attack on the rebel-held neighbourhood of al-Kalasa in the northern Syrian city of Aleppo on Thursday

Syrian rescue workers and citizens evacu...Syrian rescue workers and citizens evacuate people from a building following a reported barrel bomb attack by Syrian government forces on the central al-Fardous rebel held neighbourhood of the northern Syrian city of Aleppo, on June 9, 2015.  AFP PHOTO / KARAM AL-MASRI KARAM AL-MASRI/AFP/Getty Images

Karam Al-Masri/AFP/Getty

Syrian rescue workers and citizens evacuate people from a building following a reported barrel bomb attack by Syrian government forces on the central al-Fardous rebel held neighbourhood of the northern Syrian city of Aleppo 

A member of the civil defence sleeps on the street in the rebel-held side of Syria's northern city of Aleppo on June 8, 2015. Arabic graffiti in blue reads: "Those looking for life under the rubble of death". A couple and their five children were killed overnight in Aleppo province in strikes by the US-led coalition fighting the Islamic State group, a monitor said

Karam Al-Masri/AFP

A member of the civil defence sleeps on the street in the rebel-held side of Syria’s northern city of Aleppo on Monday. Arabic graffiti in blue reads: “Those looking for life under the rubble of death”

A rebel fighter takes position behind sandbags in Aleppo's Al-Ezaa neighbourhood...A rebel fighter takes position behind sandbags in Aleppo's Al-Ezaa neighbourhood May 20, 2015. REUTERS/Hosam Katan      TPX IMAGES OF THE DAY

Hosam Katan/Reuters

A rebel fighter takes position behind sandbags in Aleppo’s Al-Ezaa neighbourhood, Syria

A Syrian man carries a body after it was removed from the rubble of buildings following a reported barrel bomb attack by government forces on the Qadi Askar district of the northern Syrian city of Aleppo on May 20, 2015.

Zein Al-Rifai/AFP

A Syrian man carries a body after it was removed from the rubble of buildings following a barrel bomb attack by government forces on the Qadi Askar district of the northern Syrian city of Aleppo on Wednesday

A man workouts in a gym, frequented by both residents and rebel fighters, in Aleppo's al-Fardous district

Hosam Katan/Reuters

A man workouts in a gym, frequented by both residents and rebel fighters, in Aleppo’s al-Fardous district

Smoke billows following the detonation o...Smoke billows following the detonation of explosives placed by Syrian government forces inside a tunnel that was reportedly used by rebels in the government-controlled part of Aleppo on May 19, 2015. AFP PHOTO / GEORGE OURFALIANGEORGE OURFALIAN/AFP/Getty Images

George Ourfalian/AFP/Getty Images

Smoke billows following the detonation of explosives placed by Syrian government forces inside a tunnel that was reportedly used by rebels in the government-controlled part of Aleppo

A man takes pictures of civilians lying down to take cover after hearing what activists said was shelling by forces loyal to Syria's President Bashar al-Assad in Jisr al-Hajj roundabout in Aleppo

Hosam Katan/Reuters

A man takes pictures of civilians lying down to take cover after hearing shelling in Aleppo on Tuesday

Hosam Katan/Reuters

A man reacts after a barrel bomb dropped by forces loyal to Syria’s President Bashar al-Assad exploded in Aleppo’s al-Fardous district on Wednesday

A boy carries two children as he evacuates them from a site hit by what activists said was a barrel bomb dropped by forces loyal to Syria's President Bashar al-Assad in Aleppo's al-Fardous district ...A boy carries two children as he evacuates them from a site hit by what activists said was a barrel bomb dropped by forces loyal to Syria's President Bashar al-Assad in Aleppo's al-Fardous district April 2, 2015. REUTERS/Rami Zayat

Rami Zayat/Reuters

A boy carries two children as he evacuates them from a site hit by what activists said was a barrel bomb dropped by forces loyal to Syria‘s President Bashar al-Assad in Aleppo’s al-Fardous district

Opposition fighters sit inside a damaged...Opposition fighters sit inside a damaged building in the rebel-held Qastal al-Harami neighborhood, in the northern Syrian city of Aleppo, on March 24, 2015. AFP PHOTO / AMC / ZEIN AL-RIFAIZEIN AL-RIFAI/AFP/Getty Images

Zein Al-Rifaizein/AFP/Getty

Opposition fighters sit inside a damaged building in the rebel-held Qastal al-Harami neighbourhood, in the northern Syrian city of Aleppo. 

Men inspect the damage at a site hit by what activists said were two barrel bombs dropped by forces loyal to Syria's President Bashar al-Assad in Aleppo's al-Shaar neighborhood...Men inspect the damage at a site hit by what activists said were two barrel bombs dropped by forces loyal to Syria's President Bashar al-Assad in Aleppo's al-Shaar neighborhood February 26, 2015. REUTERS/Rami Zayat (SYRIA - Tags: POLITICS CIVIL UNREST CONFLICT)

Rami Zayat/Reuters

Men inspect the damage at a site hit by what activists said were two barrel bombs dropped by forces loyal to Syria‘s President Bashar al-Assad in Aleppo’s al-Shaar neighbourhood. 

A rebel fighter carries his weapon as he walks in front of a rainbow in Ratian village, north of Aleppo...A rebel fighter carries his weapon as he walks in front of a rainbow in Ratian village, north of Aleppo, after what the rebels said was an offensive against them by forces loyal to Syria's President Bashar al-Assad that attempted to advance in the village but failed to February 18, 2015. Battles in and around the Syrian city of Aleppo have killed at least 70 pro-government fighters and more than 80 insurgents after the army launched an offensive there, a monitoring group said on Wednesday. Picture taken February 18, 2015. REUTERS/Ammar Abdullah    (SYRIA - Tags: POLITICS CIVIL UNREST CONFLICT)

Ammar Abdullah/Reuters

A rebel fighter carries his weapon as he walks in front of a rainbow in Ratian village, north of Aleppo, after what the rebels said was an offensive against them by forces loyal to Syria‘s President Bashar al-Assad that attempted to advance in the village but failed.