Syria rebels build momentum with tactical successes
Over the past month, rebel forces in Syria have enjoyed tactical successes which analysts say demonstrate their growing ability to challenge the government's military dominance.
The rebels have displayed military strength and organisation in capturing several major military bases, seizing weaponry, disrupting supply lines, and forcing the military to pull back.
Capturing military bases
It is unclear how many government bases the rebels have overrun since the uprising against President Bashar al-Assad began in March 2011, mostly because they have rarely attempted to hold them because of the risk of retaliatory air strikes or ground assaults.
Analysts have in the past summed up the rebel strategy as "hit and run".
However, rebel fighters now appear to be seeking to occupy or prevent the government regaining key army and air force bases which they have captured following co-ordinated offensives, some lasting several weeks.
Such a move will help solidify rebel control over Syria's border regions, analysts say, by making it harder for government forces to deploy warplanes and heavy armour. Many opposition supporters hope that with international help such areas will become fully "liberated" and that government forces will no longer be able to operate in the north.
On 18 November, rebel forces fighting for control of Aleppo scored a major victory when they managed to overrun the base of the army's 46th Regiment at Atareb, considered a major pillar of the government's garrison in Syria's second city, after a 50-day siege.
Elias Hanna, a military analyst at the American University of Beirut, described the victory as a "tactical turning point that may lead to a strategic shift".
Two days later, the rebels strengthened their hold of the oil-rich eastern province of Deir al-Zour by capturing an artillery battalion base at Mayadin, after a three-week siege.
The base was considered one of the military's last bastions in the region, which borders Iraq. Its capture followed a series of rebel advances, including the seizure of a military airport in the same area the previous week. Two oil fields have also been taken.
Assaults have also been launched on military bases near the capital, Damascus.
On 19 November, Islamist rebels briefly captured an air defence base near the city's southern district of Hajar al-Aswad, seizing weapons and equipment before withdrawing.
Six days later, rebels overran the Marj al-Sultan air base, to the east of Damascus.
Marj al-Sultan is one of the principal facilities used by the Syrian Air Force's fleet of Mi-8 helicopters, according to Jospeh Holliday of the Institute for the Study of War in Washington. He told the New York Times that the government relied on the aircraft to resupply army units and to carry out bomb and rocket attacks, especially in the north.
Footage posted online showed damaged mobile radar stations, rebels firing rocket-propelled grenades at buildings and what appeared to be a helicopter in flames. It is not clear whether other helicopters were flown out the base before the rebels arrived.
Disrupting supply routes
The rebels have slowly cut off ground supply routes for government forces fighting in provinces to the north and east of Damascus since the spring. They have mastered the use of roadside bombs and captured several key bases, checkpoints and areas.
The capture of the 46th Regiment base to the west of Aleppo brought rebel fighters closer to connecting with their comrades-in-arms in the neighbouring province of Idlib. Days earlier, they seized the Kindi University Hospital in Aleppo, a hill-top facility which had been used by the army to close off a major road connecting Aleppo to the Turkish border.
Rebel commanders say the next and final step to cutting off government supply routes to Aleppo will be taking control of the city's airport. Security forces in the city are reportedly dependent on airlifts because the road connecting Aleppo and Damascus is under rebel control. The airport is reported to be surrounded on three sides by rebel fighters.
On 26 November, rebel fighters reportedly captured a hydroelectric dam on the River Euphrates. Activists said Tishrin Dam, east of Aleppo near the town of Manbij, was a strategic location. It is an important source of electric power and bears a major road between Aleppo and the east.
After the capture of the Mayadin military base six days earlier, one rebel commander claimed that the opposition now controlled the Euphrates valley from Deir al-Zour the Iraqi border.
The government's main focus is said to be holding Damascus and a corridor northwards through Homs and Hama to the coastal province of Latakia, a stronghold of President Assad's minority Alawite sect.
The rebels have so far failed to obtain the significant numbers of anti-aircraft weapons and armoured vehicles which their commanders say they need to repel attacks on their positions and civilians in areas under their control, and ultimately defeat government forces.
Western and regional powers have been reluctant to arm the rebels because of disunity within the main opposition coalition and the increasing presence of jihadist militants.
Weapons seized after capturing military compounds and bases have therefore been essential to the rebels' gradual transformation into forces able to challenge the government.
More important than the fall of the 46th Regiment's base, therefore, were the weapons the rebels found inside. They are reported to have captured at least three tanks, other heavy weapons and lorryloads of rifles and ammunition, including mortars, artillery shells and rockets.
Gen Ahmed al-Faj, who belongs to a joint command of rebel brigades, told the Associated Press at the time: "There has never been a battle before with this much booty."
Rebels also claimed to have seized a number of mobile anti-aircraft guns at two air defence bases outside Damascus which they recently overran, as well as at Marj al-Sultan.