A Syrian Kurdish boy sits on a destroyed tank in the Syrian town of Kobane on March 27, 2015. ISIS fighters were driven out of Kobane on January 26 by Kurdish and allied forces. #

Jaish Al-Islam (Army of Islam) brigade fighters launch a rocket towards forces loyal to Syria's President Bashar Al-Assad located beside Damascus International Airport, from the eastern Damascus suburb of Ghouta on February 24, 2015. #

Smoke rises after what activists said were air strikes by forces loyal to Syria's President Bashar al-Assad in Arbeen, in the eastern Damascus suburb of Ghouta, on March 8, 2015. #

A man carries the body of his mother after what activists said were air strikes by forces loyal to Syria's President Bashar al-Assad in Marj Al Sultan, in the eastern Damascus suburb of Ghouta on February 27, 2015. #

A general view taken on April 6, 2015, shows destruction in Yarmouk Palestinian refugee camp in the Syrian capital of Damascus. Around 2,000 people have been evacuated from the Yarmouk Palestinian refugee camp after ISIS seized large parts of it, a Palestinian official told AFP. #

Fighters loyal to Al-Qaeda's Syrian affiliate and its allies smash a statue of the late Syrian president Hafez al-Assad, father of the current President Bashar al-Assad on March 28, 2015, in the northwestern Syrian city of Idlib. A coalition made up of Al-Nusra Front, the official Syrian affiliate of Al-Qaeda, and several Islamist factions seized the city of Idlib, only the second provincial capital to be lost by the regime in more than four years of war. #

Fatima Bakkar, 83, from Syria, holds her tears as she tells her story during an interview with the Associated Press at Azraq refugee camp in Azraq, 100 kilometers (62 miles) east of Amman, Jordan, on March 10, 2015. Fatima, who is living with daughter-in-law Hamida and four grandchildren, waits for a day when they can reunite with their loved ones living in a refugee camp in Lebanon. #

People gather around a helicopter reportedly belonging to the Syrian regime forces that crashed on March 22, 2015, in Jabal al-Zawiya in the northwest province of Idlib. Islamist rebels captured four crew members when the helicopter crashed, while a fifth serviceman was killed, according to the Syrian Observatory for Human Rights. Syrian state television confirmed that a military helicopter had crashed, saying it was due to a technical failure and that search efforts to locate the crew were ongoing. #

Workers document and count dead bodies, which, according to the rebel fighters, were members of forces loyal to Syria's President Bashar al-Assad, before burying them in Aleppo on February 23, 2015. The rebel fighters said they killed the men during clashes at Raitan and al-Mallah front lines during an attempt by forces loyal to Syria's President Bashar al-Assad to encircle the northern city and cut off insurgent supply lines. #

Syrian refugee children are seen in front of their classrooms at a UNICEF school at the Al Zaatari refugee camp in the Jordanian city of Mafraq, near the border with Syria, on March 11, 2015. Jordanian officials say it is sheltering around 1.3 million Syrian refugees. #

Rebel fighters walk inside a 2nd-century Roman amphitheater in the historic Syrian southern town of Bosra al-Sham, after they took control of the area on March 25, 2015. Insurgents seized the historic town in southern Syria from the government, a group monitoring the war said, part of a counterattack rebels say they are waging to stop Damascus reclaiming the border zone near Israel and Jordan. Bosra's historic sites include an ancient citadel built around a 2nd century Roman amphitheater. It was once the capital of the Roman province of Arabia. #

Rebel fighters of al-Jabha al-Shamiya (the Shamiya Front) run with their weapons to avoid snipers north of Handarat camp in Aleppo after the group said they took control of the area from forces loyal to Syria's President Bashar al-Assad, on February 8, 2015. #

Dust rises from damaged buildings after what activists said was a mortar shell dropped on an area after air strikes by forces loyal to Syria's President Bashar al-Assad in Ain Tarma, in Eastern Ghouta, on April 5, 2015. #

A man runs with an injured child at a damaged site after what activists said was shelling by forces loyal to Syria's president Bashar al-Assad on Al-Dubeit neighborhood in Idlib city, after rebels took control of the area, on April 5, 2015. #

A Syrian man holds a wounded child as they wait for treatment at a makeshift clinic in the rebel-held area of Douma, east of the capital Damascus, following reported air strikes by regime forces on March 15, 2015. #

A man cries over the bodies of relatives after what activists said were eight air strikes by forces loyal to Syria's President Bashar al-Assad in Douma Eastern Al-Ghouta, near Damascus, on March 15, 2015. Activists said there were more than 25 dead and many more injured after the airstrikes. #

Rebel fighters dig caves in the mountains to be used as shelters from the bombing of forces loyal to Syria's President Bashar al-Assad in al-Latamna town, in the northern countryside of Hama, on March 9, 2015. #

A member of the Syrian government forces looks at enemy positions from the Fatima Hill overlooking the town of Kfar Shams, north of the southern Syrian city of Deraa on March 1, 2015, after they regained control of the hill the day before. #

Civilians walk near upright buses barricading a street, which serve as protection from snipers loyal to Syria's President Bashar al-Assad, in Aleppo's rebel-controlled Bustan al-Qasr neighborhood, on March 21, 2015. #

Residents help an injured man after what activists said was shelling from forces loyal to Syria's President Bashar al-Assad in Aleppo's Al-Mashad neighborhood on March 20, 2015. #

A female Syrian soldier from the Republican Guard commando battalion drives a tank during clashes with rebels in the restive Jobar area, in eastern Damascus, on March 25, 2015. The female battalion, which was created nearly a year ago, consists of 800 female soldiers who are positioned in the suburbs of the Syrian capital where they monitor and secure the frontlines with snipers, rockets, and machine guns. #

Rebel fighters from the Ahrar al-Sham Islamic Movement help an injured fellow fighter during what they said was an offensive to take the northwestern city of Idlib on March 24, 2015. #

Rebel fighters from Suqour al-Sham Brigade prepare a locally made shell before launching it towards forces loyal to Syria's president Bashar Al-Assad in the Idlib countryside on March 18, 2015. #

A homemade shell falls towards a building sheltering forces loyal to Syria's president Bashar Al-Assad, after being fired from rebel fighters in the Seif El Dawla neighborhood of Aleppo on March 28, 2015. #

A man holds the hand of an injured civilian in a field hospital after what activists said were air strikes by forces loyal to Syria's President Bashar al-Assad in the Douma neighborhood of Damascus on April 6, 2015. #