(01 of20)
Open Image ModalIn this Sunday Jan. 6, 2013 photo Syrian rebel fighters take their positions on the frontline of the ongoing battle for the military airport in Taftanaz, Syria. (AP Photo/Mustafa Karali) (credit:AP)
(02 of20)
Open Image ModalIn this Sunday Jan. 6, 2013 photo, an unexploded ordnance lies half-buried in the ground on the frontline of the ongoing battle for the military airport in Taftanaz, Syria. (AP Photo/Mustafa Karali) (credit:AP)
(03 of20)
Open Image ModalIn this Sunday Jan. 6, 2013 photo, a Syrian rebel fighter walks through a field on the frontline of the ongoing battle for the military airport in Taftanaz, Syria. (AP Photo/Mustafa Karali) (credit:AP)
(04 of20)
Open Image ModalIn this Friday, Jan. 11, 2013 file citizen journalism image provided by Edlib News Network, ENN, which has been authenticated based on its contents and other AP reporting, shows rebels from al-Qaida affiliated Jabhat al-Nusra waving their brigade flag as they step on the top of a Syrian air force helicopter, at Taftanaz air base. (AP Photo/Edlib News Network ENN, File) (credit:AP)
(05 of20)
Open Image ModalThis citizen journalism image provided by Edlib News Network, ENN, which has been authenticated based on its contents and other AP reporting, shows a damaged Syrian air force helicopter at Taftanaz air base, in Idlib province, northern Syria, Friday Jan. 11, 2013. (AP Photo/Edlib News Network ENN) (credit:AP)
(06 of20)
Open Image ModalIn this image taken from video obtained from Ugarit News, which has been authenticated based on its contents and other AP reporting, a statue of Hafez Assad, father of Syrian President Bashar Assad, burns after being set on fire by rebel fighters inside the grounds of the General Company of the Euphrates Dam in Al-Raqqa, Syria, Monday, Feb. 11, 2013. (AP Photo/Ugarit News via AP video) (credit:AP)
(07 of20)
Open Image ModalThis image taken from video obtained from Ugarit News, which has been authenticated based on its contents and other AP reporting, shows a Syrian fighter jet in a hangar after rebels captured Jarrah airfield in Aleppo province, Tuesday, Feb. 12, 2013. (AP Photo/Ugarit News via AP video) (credit:AP)
(08 of20)
Open Image ModalThis image taken from video obtained from Ugarit News, which has been authenticated based on its contents and other AP reporting, shows a Syrian fighter jet in a hangar after rebels captured Jarrah airfield in Aleppo province, Tuesday, Feb. 12, 2013. (AP Photo/Ugarit News via AP video) (credit:AP)
(09 of20)
Open Image ModalThis photo released by the Syrian official news agency SANA, shows flames and smoke rising from burned cars after a huge explosion that shook central Damascus, Syria, Thursday, Feb. 21, 2013. (AP Photo/SANA) (credit:AP)
(10 of20)
Open Image ModalThis photo released by the Syrian official news agency SANA, shows Syrian fire fighters extinguishing burning cars after huge explosion that shook central Damascus, Syria, Thursday, Feb. 21, 2013. (AP Photo/SANA) (credit:AP)
(11 of20)
Open Image ModalThis photo released by the Syrian official news agency SANA, shows a Syrian fire fighter extinguishing burning cars after a huge explosion that shook central Damascus, Syria, Thursday, Feb. 21, 2013. (AP Photo/SANA) (credit:AP)
(12 of20)
Open Image ModalIn this picture taken on Thursday, Feb. 21, 2013, a Free Syrian Army fighter takes his position at a previous Syrian army forces checkpoint at the main entrance of Christian village of Yacoubieh, in the northern Syrian province of Idlib, Syria. (AP Photo/Hussein Malla) (credit:AP)
(13 of20)
Open Image ModalA member of the Syrian security forces inspects the heavily damaged Zahrawi souq during a patrol in the old city of Aleppo on February 23, 2013. (STR/AFP/Getty Images) (credit:Getty Images)
(14 of20)
Open Image ModalFree Syrian Army fighters pray inside a cave at Jabal al-Zaweya in Idlib, Syria, Sunday Feb. 24, 2013. (AP Photo/Hussein Malla) (credit:AP)
(15 of20)
Open Image ModalFree Syrian Army fighters take their positions as they observe the Syrian army forces base of Wadi al-Deif, at the front line of Maarat al-Nuaman town, in Idlib province, Syria, Tuesday Feb. 26, 2013. (AP Photo/Hussein Malla) (credit:AP)
(16 of20)
Open Image ModalA Free Syrian Army fighter steps out from a hole wall to observe the Syrian army forces base of Wadi al-Deif at the front line of Maarat al-Nuaman town, in Idlib province, Syria, Tuesday Feb. 26, 2013. (AP Photo/Hussein Malla) (credit:AP)
(17 of20)
Open Image ModalA Free Syrian Army sniper takes his position as he observes the Syrian army forces base of Wadi al-Deif at the front line of Maarat al-Nuaman town, in Idlib province, Syria, Tuesday Feb. 26, 2013. (AP Photo/Hussein Malla) (credit:AP)
(18 of20)
Open Image ModalFree Syrian Army fighters from the Knights of the North brigade move to reconnaissance a Syrian army forces base of al-Karmid at Jabal al-Zaweya, in Idlib province, Syria, Wednesday, Feb. 27, 2013. (AP Photo/Hussein Malla) (credit:AP)
(19 of20)
Open Image ModalFree Syrian Army fighters from the Knights of the North brigade leave one of their caves to reconnaissance a Syrian army forces base of al-Karmid, at Jabal al-Zaweya, in Idlib province, Syria, Wednesday, Feb. 27, 2013. (AP Photo/Hussein Malla) (credit:AP)
(20 of20)
Open Image ModalCitizen journalism image provided by Coordination Committee in Kafr Susa which has been authenticated based on its contents and other AP reporting, shows people tearing down a huge poster of President Bashar Assad and hitting it with their shoes, in Raqqa, Syria, Monday, March. 4, 2013. (AP Photo/Coordination Committee In Kafr Susa) (credit:AP)