Smoke rises in the Hanano and Bustan al-Basha districts in the northern city of Aleppo as fighting continued through the night, on December 1, 2012. A large rebel force launched an offensive on one of the few army bases in northwestern Syria still in the hands of loyalist forces and as fighting near Damascus closed the main road to the airport. #

A Sukhoi-22 fighter jet of the Syrian air force drops a 500lb freefall bomb over the town of Maraat al-Numan, on November 17, 2012. After months of repeated airstrikes and artillery barrages by Syrian forces outside Maraat al-Numan, fighting for this crucial town on the Aleppo-Damascus highway shows little sign of abating. The Free Syrian Army control the town, but the Syrian army are free to bombard it at will. #

Smoke rises over the Syrian town of Ras al-Ain after an air strike, as seen from the Turkish border town of Ceylanpinar, Sanliurfa province, on November 13, 2012. A Syrian warplane struck homes in the town of Ras al-Ain on Tuesday within sight of the Turkish border, pursuing an aerial bombardment to force out rebels and drawing a new warning from Ankara. #

A Syrian man jumps over barbed wire as he tries to cross the border from the Syrian town of Ras al-Ain to the Turkish border town of Ceylanpinar, Sanliurfa province, on December 6, 2012. #

A member of Liwa (Brigade) Salahadin, a Kurdish military unit fighting alongside rebel fighters, aims at a regime fighter in the besieged district of Karmel al-Jabl in eastern Aleppo, on December 6, 2012. Protests in Syria's northern city Aleppo against the Free Syrian Army highlighted the waning influence of mainstream rebel groups and the rise of more disciplined and better-equipped radical Islamists. #

Kurdish anti-Syrian government activists parade the streets in celebration for the official declaration of liberation of the city of Derik, near al-Malikiyah, on November 15, 2012. #

Smoke and fire ascends after the Roman citadel of Kalat al-Numan was bombed by a Syrian government jet in Maaret Al-Numan in southern Idlib province, on November 20, 2012. The Roman-era town of 150,000 was virtually deserted as heavy shelling and aerial bombardments continued daily. #

A Syrian woman near a fire at a refugee camp in Azaz, Syria, on December 17, 2012. Thousands of Syrian refugees who fled their homes due to fighting between Free Syrian Army fighters and government forces, face cold weather as temperatures dropped to 2 degrees Celsius (36 degrees Fahrenheit) in Azaz. #

Abdullah Ahmed, 10, who suffered burns in a Syrian government airstrike and fled his home with his family, stands outside their tent at a camp for displaced Syrians in the village of Atmeh, Syria, on December 11, 2012. This tent camp sheltering some of the hundreds of thousands of Syrians uprooted by the country's brutal civil war has lost the race against winter: the ground under white tents is soaked in mud, rain water seeps into thin mattresses and volunteer doctors routinely run out of medicine for coughing, runny-nosed children. #

A Syrian rebel walks past Sham II, a homemade armored vehicle built by the rebels' Al-Ansar brigade, in Bishqatin, 4 km west of Aleppo, on December 8, 2012. Sham II, named after ancient Syria, is built from the chassis of a car and touted by rebels as "100 percent made in Syria." #

A Syrian rebel uses a videogame controller to activate the machine gun of Sham II, a homemade armored vehicle made by the rebels' Al-Ansar brigade, in Bishqatin, Syria, on December 8, 2012. #

Free Syrian Army fighters react after an explosion during heavy clashes with government forces at a military academy besieged by the rebels north of Aleppo, on December 15, 2012 photo. Free Syrian Army fighters took control over the military academy after battling government forces for several hours. #

The body of a Syrian Army soldier lies in a trench after heavy clashes with government forces at a military academy besieged by the rebels in Tal Sheer, Syria, on December 16, 2012. #

A Free Syrian Army fighter reacts by kissing his rifle after his comrades seized a military tank, during heavy clashes with government forces north of Aleppo, on December 15, 2012. #

A missile on the grounds of a Syrian air defense base, after Free Syrian Army fighters seized the base, in eastern Ghouta, on the eastern edge of Damascus, on November 9, 2012. #

A Syrian man smokes in a room at Dar Al-Ajaza psychiatric institution in Aleppo, on December 18, 2012. Situated in the Old City of Aleppo between Free Syrian Army and the Syrian Army positions, nearly 60 patients live in squalid conditions at the institute. Doctors who used to take care of them ran away when the war reached the city and there is a lack of food, power and medicine. Today, only three staff remain to care for the patients, who subsist on meager donations. #

Syrian rebels attend a training session in Maaret Ikhwan, near Idlib, Syria, on December 17, 2012. The training is part of an attempt to transform rag-tag rebel groups into a disciplined fighting force. #

Rebel fighters push out a boat carrying two Syrian women fleeing to Turkey through the Orontes river near the northern Syrian town of Darkush, on December 14, 2012. The United States said it planned to deploy two Patriot missile batteries to Turkey along with 400 troops to help defend its ally against potential threats from neighboring Syria. #

A Lebanese woman mourns during the funeral of Khodr Mustafa Alameddine, who was among a group of Sunni Muslims killed by the Syrian army after they crossed into Syria to fight alongside rebels, in Minieh in northern Lebanon, on December 9, 2012. The 22 men died in Tal Kalakh in the central Syrian province of Homs late last month after traveling from the northern Lebanese city of Tripoli to join the rebellion against Syrian President Bashar al-Assad, according to a local official and an Islamist leader. #

This undated photo provided by NBC News shows Richard Engel at the end of a reporting trip in Syria in July of 2012. NBC's chief foreign correspondent Richard Engel and his production team were released unharmed on Tuesday, December 18, 2012, after being held captive for five days inside Syria by an "unknown group," the network says. #

Abu Faez, age 58, who served in the Syrian army as an officer between 1970 and 2002, mans a BMP personnel carrier in Free Syrian Army operations against the Syrian government army, in Maarat al-Numan, on November 17, 2012. #

A member of Liwa (Brigade) Salahadin, a Kurdish military unit fighting alongside rebel fighters, monitors the area in the besieged district of Karmel al-Jabl in eastern Aleppo, on December 6, 2012. #

Night falls on a Syrian-rebel controlled area on Sa'ar street. An apartment is illuminated by fire used by one family to keep them warm beside destroyed buildings, among those the Dar Al-Shifa hospital, after airstrikes targeted the area last week, in Aleppo, on November 29, 2012. #

Syrian rebels celebrate next to the remains of a Syrian government fighter jet which was shot down at Daret Ezza, on the border between the provinces of Idlib and Aleppo, on November 28, 2012. Syrian rebels captured the pilot, witnesses told an AFP reporter in the town. #

A woman asks a Free Syrian Army fighter to sell her bread, in Maaret Misreen, near Idlib, Syria, on December 13, 2012. The town is broke, relying on a slowing trickle of local donations. The rebels, a motley crew of laborers, mechanics and shopowners, have little experience in government. President Bashar Assad's troops still control the city of Idlib a few miles away, making area roads unsafe and keeping Maaret Misreen cut off from most of Syria. #

Free Syrian Army fighters from Al-Farooq battalion remove a poster of Syria's President Bashar Al-Assad from a military hospital after the fighters said they fought and defeated government troops in Halfaya, near Hama, on December 18, 2012. #

Buildings damaged by what activists said were missiles fired by a Syrian Air Force fighter jet loyal to President Bashar al-Assad, in Daraya, near Damascus, on December 10, 2012. #

A Free Syrian Army fighter, who was severely injured during fighting with government forces, is treated by doctors in an ambulance on the way to Kilis Hospital in Turkey, at the Bab Al-Salameh border crossing, on December 10, 2012. #