Syrian government forces and rebels were waging a fierce battle Saturday for control of a strategic crossroads in a southern Syrian town, according to opposition activists and official accounts.
Fighters affiliated with the Southern Front, a West-backed grouping of rebel factions, say they have pushed back government forces attempting to wrest control of Sheik Maskin, a rebel-held town in Dara province about 50 miles south of Damascus, the capital and seat of power of embattled President Bashar Assad.
Syrian government forces have repeatedly thwarted rebels' efforts to secure a corridor from the south to Damascus for an eventual assault on the heavily defended capital.
Sheik Maskin, once home to 25,000 people, is considered pivotal because it is near major highways leading to Damascus, the Jordanian border and other areas in the south.
The Syrian Media Organization, the press arm of the Southern Front rebels, reported last week that fighters "had repulsed Assad's forces who tried to advance on the northern neighborhood of the town of Sheik Maskin."
On Friday, Syrian state media said that army units closing in on Sheik Maskin had advanced to within artillery range of the "terrorists," the Syrian government's term for antigovernment rebels.
Opposition activists reported intensified government bombardment in and around Sheik Maskin and the arrival of battle-tested loyalist reinforcements.
Fighting along with U.S.-backed rebels were elements of Al Nusra Front, the official Al Qaeda affiliate in Syria.
In a Facebook posting, Al Nusra supporters reported "vicious battles" in the Sheik Maskin area. Earlier posts also eulogized a prominent Al Nusra commander, Abu Humam Jazrawi, who was killed in the fighting.
Al Nusra's participation illustrates how Western-supported rebel groups often cooperate with the Al Qaeda franchise, though both sides try to play down the extent of coordination. Recent clashes between Al Nusra Front and U.S.-backed rebels in northwestern Syria do not appear to have broken the de facto alliance between the Al Qaeda affiliate and West-backed fighters in the south.
In August, Al Nusra fighters also spearheaded an assault that wrested control of the Quneitra crossing between Syria and the Israeli-occupied Golan Heights.
A Southern Front spokesman confirmed Al Nusra's presence in Sheik Maskin but maintained that only a small number of Al Nusra fighters had taken part.
U.S.-backed insurgents in southern Syria insist they represent a model that, if provided with sufficient U.S. and other foreign support, could challenge Assad's power.
More than three years of punishing conflict have left a complex patchwork of rebel-held territory across Syria split among various factions, including many hard-core Islamists and warlords.
Islamic State, an Al Qaeda breakaway faction, controls vast stretches of land in northern and eastern Syria and in neighboring Iraq. But Islamic State is not a major presence in the south, rebel commanders say. U.S. warplanes have been targeting Islamic State positions for more than two months.
The fractured state of the Syrian opposition has aided the government's slow but inexorable advance on a number of fronts, including the suburbs of Damascus, the central province of Homs and the northern city of Aleppo. But the opposition says it is stronger and better-organized in southern Syria, which has access to supplies and fighters entering Syria from neighboring Jordan, a major U.S. ally.
Jordan is also home to the Military Operations Center, an opposition logistics and supply hub in Amman staffed by a number of Western intelligence operatives, including CIA officers, according to opposition commanders. (The CIA has declined to comment.)
Sheik Maskin, along with the nearby towns of Nawa and Izra, is seen as key to controlling the southern-most approaches to Damascus.
Of the three towns, according to opposition accounts, only heavily fortified Izra remains firmly in government hands.
Yet the situation in Izra may also be tenuous for the Syrian army. A pro-government Facebook page, "Wounded Nawa," reported that rebels had advanced to within three miles of Izra, and warned of a possible collapse of government forces. The page's contents could not be independently verified.
Regardless, a direct rebel attack on Damascus from the south is a long way off. Any forces assaulting the capital would still have to contend with the Syrian army's 9th division, stationed near the town of Sanamayn, 30 miles south of Damascus. The government has also deployed crack military units and elements of Hezbollah, the Lebanese militia, to defend the capital.
For months, Syrian army and allied fighters have been deployed in force to cut off supply routes from rebel strongholds in the south to opposition forces on the outskirts of Damascus. Syrian forces have reported several ambushes of rebel units along the route that have left many of the rebels dead.
Special correspondent Bulos reported from Amman and Times staff writer McDonnell from Beirut.