In the three years since the Syrian crisis began on 15 March 2011, more than 100,000 people have been killed. A third of the country's population has been forced to leave their homes, with an estimated 2.5 million people fleeing the country. 

IBTimesUK looks back at 25 powerful images from three years of bloody conflict.

June 15, 2011: A Syrian woman walks near tents at a refugee camp in the Turkish border town of Boynuegin. More than 8,500 Syrians had already fled to neighbouring Turkey to escape the widening military campaign to crush protests against President Bashar al-Assad
June 15, 2011: A Syrian woman walks near tents at a refugee camp in the Turkish border town of Boynuegin. More than 8,500 Syrians had already fled to neighbouring Turkey to escape the widening military campaign to crush protests against President Bashar al-AssadReuters
May 10, 2012: People run carrying a burnt body at the site of an explosion in Damascus
May 10, 2012: People run carrying a burnt body at the site of an explosion in DamascusReuters
May 26, 2012: People gather at a mass burial for the victims reportedly killed during an artillery barrage from Syrian forces in Houla. UN observers in Syria confirmed that artillery and tank shells were fired at a residential area, where at least 108 people, including many children, were killed
May 26, 2012: People gather at a mass burial for the victims reportedly killed during an artillery barrage from Syrian forces in Houla. UN observers in Syria confirmed that artillery and tank shells were fired at a residential area, where at least 108 people, including many children, were killedReuters
Civil defence members put out a fire at the site of an explosion in the southern suburbs of Beirut
Civil defence members put out a fire at the site of an explosion in the southern suburbs of BeirutReuters
August 4, 2012: A Free Syrian Army fighter reacts after his friend was shot by Syrian Army soldiers during clashes in the Salah al-Din neighbourhood in central Aleppo
August 4, 2012: A Free Syrian Army fighter reacts after his friend was shot by Syrian Army soldiers during clashes in the Salah al-Din neighbourhood in central AleppoReuters
August 7, 2012: A Free Syrian Army fighter screams in pain after he was injured in his leg by shrapnel from a shell fired from a Syrian Army tank in the Salaheddine neighbourhood of central Aleppo
August 7, 2012: A Free Syrian Army fighter screams in pain after he was injured in his leg by shrapnel from a shell fired from a Syrian Army tank in the Salaheddine neighbourhood of central AleppoReuters
August 9, 2012: A Syrian Air Force fighter plane fires a rocket during an air strike in the village of Tel Rafat, north of Aleppo
August 9, 2012: A Syrian Air Force fighter plane fires a rocket during an air strike in the village of Tel Rafat, north of AleppoReuters
August 16, 2012: A Free Syrian Army fighter carries the body of a fellow rebel during clashes in Aleppo
August 16, 2012: A Free Syrian Army fighter carries the body of a fellow rebel during clashes in AleppoReuters
December 19, 2012: An unexploded ordnance is seen on a street in the Ain Terma area in Ghouta, east of Damascus
December 19, 2012: An unexploded ordnance is seen on a street in the Ain Terma area in Ghouta, east of DamascusReuters
Ayman al-Sahili, a Reuters cameraman, reacts as he was shot in the leg while filming on the front line in Aleppo by a sniper loyal to Syrian President Bashar el-Assad on 31 December 2012
Ayman al-Sahili, a Reuters cameraman, reacts as he was shot in the leg while filming on the front line in Aleppo by a sniper loyal to Syrian President Bashar el-Assad on 31 December 2012Reuters
January 3, 2013: A father in Aleppo reacts after the death of two of his children, whom activists said were killed by shelling by forces loyal to Syria's President Bashar al-Assad
January 3, 2013: A father in Aleppo reacts after the death of two of his children, whom activists said were killed by shelling by forces loyal to Syria's President Bashar al-AssadReuters
January 30, 2013: Free Syrian Army fighters run for cover as a tank shell explodes during heavy fighting in the Ain Tarma neighbourhood of Damascus
January 30, 2013: Free Syrian Army fighters run for cover as a tank shell explodes during heavy fighting in the Ain Tarma neighbourhood of DamascusReuters
February 14, 2013: A former Free Syrian Army fighter buries his dead four-day-old son in Arshaf village near Aleppo. The child was born with breathing difficulties, his grandmother said, and due to a lack of medical services and doctors in Syria, he did not receive medical attention until two days after he was born
February 14, 2013: A former Free Syrian Army fighter buries his dead four-day-old son in Arshaf village near Aleppo. The child was born with breathing difficulties, his grandmother said, and due to a lack of medical services and doctors in Syria, he did not receive medical attention until two days after he was bornReuters
Um Jaafar, a woman fighter in the Free Syrian Army, sits with other women undergoing military training in Aleppo
Um Jaafar, a woman fighter in the Free Syrian Army, sits with other women undergoing military training in AleppoReuters
March 13, 2013: A boy looks inside the toppled statue of President Bashar Al-Assad's father, Hafez Al-Assad, in Raqqa province, eastern Syria
March 13, 2013: A boy looks inside the toppled statue of President Bashar Al-Assad's father, Hafez Al-Assad, in Raqqa province, eastern SyriaReuters
June 17, 2013: Men ride on a motorbike as a Free Syrian Army fighter walks near damaged buildings in Kefr Hamra, Aleppo
June 17, 2013: Men ride on a motorbike as a Free Syrian Army fighter walks near damaged buildings in Kefr Hamra, AleppoReuters
July 18, 2013:An aerial view shows the Zaatari refugee camp, holding roughly 115,000 Syrian refugees, near the Jordanian city of Mafraq
July 18, 2013:An aerial view shows the Zaatari refugee camp, holding roughly 115,000 Syrian refugees, near the Jordanian city of MafraqReuters
August 19, 2013: A man walks inside the damaged historical old souk in Homs
August 19, 2013: A man walks inside the damaged historical old souk in HomsReuters
August 21, 2013: Syrian activists inspect the bodies of people they say were killed by nerve gas in the Ghouta region, in the Duma neighbourhood of Damascus
August 21, 2013: Syrian activists inspect the bodies of people they say were killed by nerve gas in the Ghouta region, in the Duma neighbourhood of DamascusReuters
October 17, 2013: A Free Syrian Army fighter fires an anti-tank missile towards what the FSA said were locations controlled by forces loyal to Syria's President Bashar al-Assad in the eastern Hama countryside
October 17, 2013: A Free Syrian Army fighter fires an anti-tank missile towards what the FSA said were locations controlled by forces loyal to Syria's President Bashar al-Assad in the eastern Hama countrysideReuters
October 20, 2013: Residents run from a fire at a petrol and oil shop in Aleppo's Bustan Al-Qasr neighbourhood. Witnesses said the fire was caused by a bullet fired by a sniper loyal to Syrian President Bashar al-Assad at the Karaj al-Hajez crossing, a passageway separating Aleppo's Bustan al-Qasr, which is under the rebels' control and Al-Masharqa neighborhood, an area controlled by the regime
October 20, 2013: Residents run from a fire at a petrol and oil shop in Aleppo's Bustan Al-Qasr neighbourhood. Witnesses said the fire was caused by a bullet fired by a sniper loyal to Syrian President Bashar al-Assad at the Karaj al-Hajez crossing, a passageway separating Aleppo's Bustan al-Qasr, which is under the rebels' control and Al-Masharqa neighborhood, an area controlled by the regimeReuters
December 28, 2013: A man stands in a building damaged by what activists said were air strikes from forces loyal to Syria's President Bashar al-Assad in the Maysar neighbourhood of Aleppo
December 28, 2013: A man stands in a building damaged by what activists said were air strikes from forces loyal to Syria's President Bashar al-Assad in the Maysar neighbourhood of AleppoReuters
January 7, 2014: Men help a wounded boy who survived what activists say was an airstrike by forces loyal to Syrian President Bashar al-Assad in the Duma neighbourhood of Damascus
January 7, 2014: Men help a wounded boy who survived what activists say was an airstrike by forces loyal to Syrian President Bashar al-Assad in the Duma neighbourhood of DamascusReuters
 January 31, 2014: Thousands of residents wait to receive food aid distributed by the UN Relief and Works Agency (UNRWA) at the al-Yarmouk camp, south of Damascus, Syria
 January 31, 2014: Thousands of residents wait to receive food aid distributed by the UN Relief and Works Agency (UNRWA) at the al-Yarmouk camp, south of Damascus, SyriaUNRWA
March 6, 2014: A survivor sits on the rubble of collapsed buildings 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-Sakhour district
March 6, 2014: A survivor sits on the rubble of collapsed buildings 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-Sakhour districtReuters