White House: Syria crosses ‘red line’ with use of chemical weapons on its people

Barbara Starr, Jessica Yellin and Chelsea J. Carter, CNN
Updated 8:42 AM EDT, Fri June 14, 2013
In this photo provided by the anti-government activist group Aleppo Media Center, Syrian men help survivors out of a building in Aleppo after it was bombed, allegedly by a Syrian regime warplane on Saturday, February 8. The United Nations estimates more than 100,000 people have been killed since the Syrian conflict began in March 2011. Click through to see the most compelling images taken during the conflict, which is now a civil war:
Syrian civil war in photos —
In this photo provided by the anti-government activist group Aleppo Media Center, Syrian men help survivors out of a building in Aleppo after it was bombed, allegedly by a Syrian regime warplane on Saturday, February 8. The United Nations estimates more than 100,000 people have been killed since the Syrian conflict began in March 2011. Click through to see the most compelling images taken during the conflict, which is now a civil war:
Aleppo Media Center AMC/AP
Syrians gather at a site hit by barrel bombs, allegedly dropped by a regime helicopter on the opposition-controlled Mesekin Hananu district of Aleppo on February 8.
Syrian civil war in photos —
Syrians gather at a site hit by barrel bombs, allegedly dropped by a regime helicopter on the opposition-controlled Mesekin Hananu district of Aleppo on February 8.
Mustafa Sultan/Anadolu Agency/Getty Images
Civilians wave national flags as they take part in a rally in support of Syrian President Bashar al-Assad in Damascus, in a handout photo released by the official Syrian Arab News Agency on February 8.
Syrian civil war in photos —
Civilians wave national flags as they take part in a rally in support of Syrian President Bashar al-Assad in Damascus, in a handout photo released by the official Syrian Arab News Agency on February 8.
AFP/Getty Images
A man stands next to debris in the road following a reported airstrike by Syrian government forces in the northern city of Aleppo on February 8.
Syrian civil war in photos —
A man stands next to debris in the road following a reported airstrike by Syrian government forces in the northern city of Aleppo on February 8.
MOHAMMED WESAM/AFP/Getty Images
Medical personnel look for survivors after a reported airstrike in Aleppo, Syria, on Saturday, February 1.
Syrian civil war in photos —
Medical personnel look for survivors after a reported airstrike in Aleppo, Syria, on Saturday, February 1.
MOHAMMED AL-KHATIEB/AFP/Getty Images
Syrians carry a dead body following an airstrike on February 1.
Syrian civil war in photos —
Syrians carry a dead body following an airstrike on February 1.
ZEIN AL-RIFAI/AFP/Getty Images
A man walks amid debris and dust on January 31.
Syrian civil war in photos —
A man walks amid debris and dust on January 31.
AFP PHOTO/MOHAMMED AL-KHATIEB/getty images
An injured man is covered in dust after an airstrike on January 29.
Syrian civil war in photos —
An injured man is covered in dust after an airstrike on January 29.
MOHAMMED AL-KHATIEB/AFP/Getty Images
A man tries to fix electrical wires in a neighborhood of Aleppo, Syria, on January 27.
Syrian civil war in photos —
A man tries to fix electrical wires in a neighborhood of Aleppo, Syria, on January 27.
STRinger/AFP/Getty Images
Rebels and civilians check out a crater that activists say resulted from a Syrian government airstrike on an Aleppo bus station on Tuesday, January 21.
Syrian civil war in photos —
Rebels and civilians check out a crater that activists say resulted from a Syrian government airstrike on an Aleppo bus station on Tuesday, January 21.
AMMAR ABDULLAH/REUTERS/LANDOV
Men rush to a site that Syrian government forces reportedly hit in Aleppo on January 21.
Syrian civil war in photos —
Men rush to a site that Syrian government forces reportedly hit in Aleppo on January 21.
STRINGER/reuters/LANDOV
Buildings lie in ruins in Aleppo on Sunday, January 19, after reported air raids by Syrian government planes.
Syrian civil war in photos —
Buildings lie in ruins in Aleppo on Sunday, January 19, after reported air raids by Syrian government planes.
MOHAMMED WESAM/AFP/Getty Images
A Syrian child collects items from a garbage pile on Saturday, January 18, in Douma, northeast of the capital.
Syrian civil war in photos —
A Syrian child collects items from a garbage pile on Saturday, January 18, in Douma, northeast of the capital.
MAJD ALDEEK/AFP/Getty Images
A piece of exploded mortar lies in a street in Daraya, a city southwest of Damascus, on Friday, January 17.
Syrian civil war in photos —
A piece of exploded mortar lies in a street in Daraya, a city southwest of Damascus, on Friday, January 17.
FADI DIRANI/AFP/Getty Images
Residents search for survivors in Aleppo on Saturday, December 28, 2013, after what activists said were airstrikes by forces loyal to Syrian President Bashar al-Assad.
Syrian civil war in photos —
Residents search for survivors in Aleppo on Saturday, December 28, 2013, after what activists said were airstrikes by forces loyal to Syrian President Bashar al-Assad.
STRINGER/reuters/LANDOV
A man appears distraught after an air raid in Aleppo on Monday, December 23.
Syrian civil war in photos —
A man appears distraught after an air raid in Aleppo on Monday, December 23.
Saad Abobrahim/Reuters/Landov
Free Syrian Army fighters sit in a damaged house in Old Aleppo on Saturday, December 21.
Syrian civil war in photos —
Free Syrian Army fighters sit in a damaged house in Old Aleppo on Saturday, December 21.
Abdalrhman Ismail/Reuters/Stringer/Landov
People search for survivors amid the rubble after an airstrike in Aleppo on Tuesday, December 17.
Syrian civil war in photos —
People search for survivors amid the rubble after an airstrike in Aleppo on Tuesday, December 17.
MOHAMMED AL-KHATIEB/AFP/Getty Images
A man sits on the ground after the airstrike in Aleppo on December 17.
Syrian civil war in photos —
A man sits on the ground after the airstrike in Aleppo on December 17.
MOHAMMED AL-KHATIEB/AFP/Getty Images
A woman carries children following airstrikes on a rebel area of Aleppo on Sunday, December 15.
Syrian civil war in photos —
A woman carries children following airstrikes on a rebel area of Aleppo on Sunday, December 15.
MOHAMMED AL-KHATIEB/AFP/Getty Images
Syrians look at the aftermath of an airstrike on a rebel area of Aleppo on December 15.
Syrian civil war in photos —
Syrians look at the aftermath of an airstrike on a rebel area of Aleppo on December 15.
MOHAMMED AL-KHATIEB/AFP/Getty Images
Syrians help a wounded woman following airstrikes in Aleppo on December 15.
Syrian civil war in photos —
Syrians help a wounded woman following airstrikes in Aleppo on December 15.
MOHAMMED AL-KHATIEB/AFP/Getty Images
Syrians look at the aftermath of an airstrike on a rebel area of Aleppo on December 15.
Syrian civil war in photos —
Syrians look at the aftermath of an airstrike on a rebel area of Aleppo on December 15.
MOHAMMED AL-KHATIEB/AFP/Getty Images
Syrian rebel fighters clash with pro-government forces in Aleppo on Wednesday, December 11.
Syrian civil war in photos —
Syrian rebel fighters clash with pro-government forces in Aleppo on Wednesday, December 11.
MEDO HALAB/AFP/Getty Images
A woman weeps inside a damaged vehicle after forces loyal to President Bashar al-Assad captured the town of Nabak on Monday, December 9.
Syrian civil war in photos —
A woman weeps inside a damaged vehicle after forces loyal to President Bashar al-Assad captured the town of Nabak on Monday, December 9.
STRinger/AFP/Getty Images
A rebel fighter takes position during fighting with government forces in Deir Ezzor on Monday, December 2.
Syrian civil war in photos —
A rebel fighter takes position during fighting with government forces in Deir Ezzor on Monday, December 2.
AHMAD ABOUD/AFP/Getty Images
Shiite fighters from a group called the Hussein Brigade search for rebels from the Free Syrian Army in Hejeira on Thursday, November 21.
Syrian civil war in photos —
Shiite fighters from a group called the Hussein Brigade search for rebels from the Free Syrian Army in Hejeira on Thursday, November 21.
Jaber al-Helo/AP
Free Syrian Army rebels battle government forces in Aleppo on Monday, November 18.
Syrian civil war in photos —
Free Syrian Army rebels battle government forces in Aleppo on Monday, November 18.
KARAM AL-MASRI/AFP/Getty Images
A rebel fighter holds his position in a damaged building during clashes with government forces in Deir Ezzor on Monday, November 11.
Syrian civil war in photos —
A rebel fighter holds his position in a damaged building during clashes with government forces in Deir Ezzor on Monday, November 11.
AHMAD ABOUD/AFP/Getty Images
A rebel fighter fires during clashes with government forces in Deir Ezzor on November 11.
Syrian civil war in photos —
A rebel fighter fires during clashes with government forces in Deir Ezzor on November 11.
AHMAD ABOUD/AFP/Getty Images
A rebel fighter prepares an improvised mortar shell in Aleppo, Syria, on Saturday, November 9.
Syrian civil war in photos —
A rebel fighter prepares an improvised mortar shell in Aleppo, Syria, on Saturday, November 9.
FOUAD HALLAK/AFP/Getty Images
Two injured men are transported on a cart in Aleppo, Syria, following shelling as fighting between pro-government forces and rebels continues on Saturday, October 26.
Syrian civil war in photos —
Two injured men are transported on a cart in Aleppo, Syria, following shelling as fighting between pro-government forces and rebels continues on Saturday, October 26.
KARAM AL-MASRI/AFP/Getty Images
Rebel fighters hold a position in Deir Ezzor, Syria, on Thursday, October 24.
Syrian civil war in photos —
Rebel fighters hold a position in Deir Ezzor, Syria, on Thursday, October 24.
Ahmad Aboud/AFP/Getty Images
An opposition fighter stands in the doorway of a building as he smokes a cigarette in Deir Ezzor, Syria, on Tuesday, October 22.
Syrian civil war in photos —
An opposition fighter stands in the doorway of a building as he smokes a cigarette in Deir Ezzor, Syria, on Tuesday, October 22.
Ahmad Aboud/AFP/Getty Images
People use buckets as they try to extinguish a fire that ignited at a fuel station in Aleppo, Syria, on Sunday, October 20.
Syrian civil war in photos —
People use buckets as they try to extinguish a fire that ignited at a fuel station in Aleppo, Syria, on Sunday, October 20.
KARAM AL-MASRI/AFP/Getty Images
A Syrian opposition fighter aims a catapult toward regime forces in Aleppo, Syria, on Thursday, October 17.
Syrian civil war in photos —
A Syrian opposition fighter aims a catapult toward regime forces in Aleppo, Syria, on Thursday, October 17.
KARAM AL-MASRI/AFP/Getty Images
Firefighters extinguish a burning vehicle after two mortar rounds struck the Abu Roumaneh area in Damascus, Syria, on Saturday, October 12.
Syrian civil war in photos —
Firefighters extinguish a burning vehicle after two mortar rounds struck the Abu Roumaneh area in Damascus, Syria, on Saturday, October 12.
ap
An opposition fighter aims as others run for cover while they hold a position behind burning tires in the Salaheddin district of the northern Syrian city of Aleppo on Wednesday, October 9.
Syrian civil war in photos —
An opposition fighter aims as others run for cover while they hold a position behind burning tires in the Salaheddin district of the northern Syrian city of Aleppo on Wednesday, October 9.
TAREK ABU Al-FAHEM/AFP/Getty Images
An opposition fighter smokes a cigarette as he takes a break following the injury of his friend in the Salaheddin neighborhood of Aleppo on October 9.
Syrian civil war in photos —
An opposition fighter smokes a cigarette as he takes a break following the injury of his friend in the Salaheddin neighborhood of Aleppo on October 9.
KARAM AL-MASRI/AFP/Getty Images
Smoke rises after a mortar shell hit a residential area during fighting between Syrian government forces and rebels in Maaret al-Numan, Syria, on October, 9.
Syrian civil war in photos —
Smoke rises after a mortar shell hit a residential area during fighting between Syrian government forces and rebels in Maaret al-Numan, Syria, on October, 9.
AP
Rebel fighters cover a car in mud for camouflage at an undisclosed location in Syria's northwestern province of Idlib on Tuesday, October 8.
Syrian civil war in photos —
Rebel fighters cover a car in mud for camouflage at an undisclosed location in Syria's northwestern province of Idlib on Tuesday, October 8.
MOHAMAD JADAAN/AFP/Getty Images
Masked female rebel fighters walk alongside their trainer on a street in the Salaheddin district of Aleppo, Syria, on October 8.
Syrian civil war in photos —
Masked female rebel fighters walk alongside their trainer on a street in the Salaheddin district of Aleppo, Syria, on October 8.
KARAM AL-MASRI/AFP/Getty Images
A rebel fighter prays moments before heading into battle in Maaret al-Numan, Syria, on Monday, October 7.