The Qalamoun offensive (May–June 2015) was an offensive led by the Iranian-backed Shia militia Hezbollah, supported by the Syrian Arab Army, during the Syrian civil war, against Sunni Islamist al-Nusra Front and other Syrian opposition forces entrenched in the mountains of the Qalamoun region.
Background
In mid-November 2013, the Syrian military, backed by Hezbollah, launched an offensive against the rebel-held Qalamoun Mountains in an attempt to cut rebel supply lines to Damascus from Lebanon. The strategic region had been used by rebel forces as a rear base for its operations around the capital Damascus. The battle was primarily led on the rebel side by al-Nusra Front. By late April 2014, the last major rebel stronghold in the region fell to the Syrian Army, as it secured all of the towns in the region. However, 3,000 rebels retreated into the mountains to conduct guerrilla hit-and-run attacks.
From June through August 2014, a new Syrian government offensive against remnant rebel forces led to the rebels coming under siege. Over the following months, al- Front and the Islamic State of Iraq and the Levant maintained a foothold in the region's rugged terrain. Over 20 FSA factions merged into the Gathering of Western Qalamoun group, while by the end of the year, six eastern Qalamoun FSA brigades formed the Mujahideen Shura Council. At the same time, the arrival of an ISIL expeditionary force lead to a wave of FSA defections into ISIL numbering in the hundreds, further boosting the Islamic State's presence in the region, which reached approximately 1,000 fighters. Al- Front maintained 600 militants in Qalamoun's eastern areas, forging an alliance with ISIL in the region.
The offensive Prelude Between 25 and 28 March 2015, the Syrian Army and Hezbollah captured two hills near the town of Flitah and several others in the Zabadani region. The fighting left 30 rebels dead. The Lebanese Army seized some positions on the outskirts of Arsal from jihadist fighters. By 3 April, the Syrian military had advanced on three axes towards Zabadani, securing the western and eastern approaches to the city, and relatively paralyzing the defending rebels. Fifteen al-Nusra Front fighters attempting to reinforce the rebels in Zabadani were killed trying to breach the cordon.
In mid-April, opposition forces captured a strategic hill overlooking Flita that had been held by Hezbollah fighters. At this time, Hezbollah was preparing for a new offensive, considered to be a decisive battle for Qalamoun, while the rebels were making efforts to unite different warring opposition groups in an effort to take control of the Qalamoun region. However, ISIL and al-Nusra Front were still competing to win over communities in the Arsal area and the rebels in both Zabadani's mountains range and in the Anti-Lebanon Mountains switched from offense to defense. They were preparing trenches, tunnels, bunkers, and barricades, in anticipation of a possible battle in the spring.
On the morning on 25 April 2015, explosions targeted the Brigade 155 (main Syrian Scud missile-base) and Brigade 65 bases in Qalamoun. Two weapons convoys were also targeted, reportedly killing one person. According to an opposition source, the targets were Hezbollah camps and ammo storages within the two bases. Several explosions were heard in the areas of Kteife, Yabrud and a village in Qalamoun. Plumes of smoke were seen above the Brigade 65 base, shortly after the strikes.
According to conflicting sources, the attack was attributed to a ground attack by al-Nusra Front, or an air operation of the Israeli Air Force. Unprecedently, unlike previous cases of no comment, Israeli official sources denied any involvement of Israeli forces in the incident.
Operations begin
Early on 4 May, al-Nusra Front and allied Islamists launched a preemptive attack against SAA and Hezbollah forces, and by the next day captured several positions. The aim of the assault was to capture the border-crossing into Lebanon near Assal al-Ward. At the same time, Hezbollah ambushed an al-Nusra Front convoy near Tfail, killing 15 and wounding 30 militants.
On the morning of 6 May, heavy fighting erupted along the border near Assal al-Ward. On 7 May, Hezbollah launched a series of limited and quick operations from the Lebanese side of the border, while Syrian Army operations commenced from the Syrian side. Two days after the fighting at Assad al-Ward started, the Syrian Army and Hezbollah seized control of a number of hilltops overlooking Assal al-Ward, reportedly killing dozens of rebels and securing the town. Hezbollah fighters advancing from Assal al-Ward linked up with fighters coming from the outskirts of the Lebanese village of Brital. In addition, government forces separated rebels at Zabadani from those in the mountains, severing their logistical lines, and putting both under separate blockades.
On 9 May, a military source claimed government forces captured three villages in the Jour Al-'Anib area.
Rebels abandoned their camps in a hurry in the face of the Hezbollah advance and left groceries, medicines and other supplies which littered their camps. Thousands of retreating rebels were expected to flee towards the Lebanese town of Arsal, after pulling back first to the outskirts of Ras al-Maara. The withdrawing militants also reportedly left behind 150 heavy machine guns (from 12.7 to 23 mm caliber) and anti-tank rockets (firing range from 3.5 to 5 kilometers). The quick collapse and retreat of some 2,000 al-Nusra Front fighters was attributed to a "lack of sufficient experience in direct fighting", according to a Salafi sheikh who maintained contacts with al-Nusra Front and ISIL.
On 11 May, the Army and Hezbollah captured Al-Barouh hill outside Al-Juba, taking total control of the outskirts of the village, and seized the border-crossing at Ma'br Al-Kharbah. In addition, military sources reported government troops captured five small villages in the region. Hezbollah advances were also confirmed by the pro-opposition SOHR group.
Despite the fighting taking place over the previous week, an all-out battle had reportedly not yet started, with some predictions of it happening in the second half of the month. ISIL forces, entrenched six kilometers away near Arsal, had also not yet joined the fighting. However, ISIL commanders from Iraq were reportedly brought in for the upcoming battle with Hezbollah.
On 12 May, al-Nusra Front and its allies vowed to "eradicate" ISIL in the Qalamoun region, after ISIL reportedly "betrayed" their rebel allies and attacked several of their bases in the border area, as well as blocking rebel transport routes. According to Mario Abou Zeid from Beirut's Carnegie Middle East Center, Syrian Intelligence directed its operatives within ISIL in Qalamoun to launch probing skirmishes against FSA forces to test their defenses, and in an attempt to distract them from the main battle.
Meanwhile, the Syrian Army and Hezbollah reportedly seized more areas between Ras al-Maara and the Lebanese village of Nahleh. During their operations, Hezbollah used unmanned drones. According to the SOHR, eight Hezbollah militants were killed in the Qalamoun mountains between 11 and 12 May. The retreating rebels were reportedly concentrated on the mountain's highest hilltop, Tallat Mussa. Still, the day's fighting was lighter due to intermittent rainfall and fog.
Capture of Tallat Mussa On 13 May, the Syrian Army and Hezbollah took full control of Tallat Mussa after capturing at least nine rebel positions during heavy exchanges of artillery and rocket fire along the ridge between Al-Juba, Ras al-Maara and Assal al-Ward. Earlier in the day, Army troops, backed up by Hezbollah, seized half of the outskirts of Ras al-Maara and advanced toward the highlands of Jabal al-Barouh which is linked to Tallat Mussa. Surviving rebel fighters were pushed towards the outskirts of Arsal. The night of the assault on Tallat Mussa, temperatures reached zero degrees Celsius as it rained and hailed. Before taking the mountain top, Syrian Army soldiers had to climb up the slopes under heavy mortar and sniper fire. According to the SOHR, 36 rebels, 18 Hezbollah and 13 NDF fighters were killed during the fighting, while Lebanese security sources put the death toll at 53 rebels and four Hezbollah fighters. The capture of the hilltop was described by Elijah J. Magnier as the beginning of the long-announced battle. The Syrian Army also claimed to have captured the hills of al-Jerafah, Sin al-Sakhrey, al-Reya, Ouqbet al-Faseh, and all of the barrens of Ras al-Maara.
Fighting for the Jubbah Heights and Tal Thaljah On the next day, Hezbollah swept areas around Tallat Mussa for any remaining pockets of rebels, as it entered the final stage of the offensive. Hezbollah clashed with militants at Jabal al-Barouh, while it took control of the Ras al-Marra-Arsal border-crossing, which was the last border entry into Qalamoun from Lebanon, as well as Dahr al-Hawa Hill, which overlooks Arsal and Younin. In addition, the SAA and NDF launched an attack on al-Nusra Front reinforcements coming from the Jubbah Heights. On the same day, ISIL and al-Nusra Front engaged in fierce clashes along the Lebanese side of the border, after ISIL attempted to infiltrate al-Nusra Front positions in al-Zamarani and Wadi Ajram. ISIL's first attack wave around 5 P.M. was repelled by heavy artillery fire, but in the evening, ISIL launched a second attack that led to fierce fighting. The second attack was also eventually repelled, with ISIL fighters retreating to the north.
On 15 May, Hezbollah captured Jabal al-Barouh. In the evening, al-Nusra Front's frontline at Ras Al-Marra reportedly collapsed, after Hezbollah, in coordination with the SAA and NDF, captured the Ras Al-Marra barrens. In addition, Jabal Al-'Arteez was also seized. A victory speech by the Hezbollah leader Hassan Nasrallah was announced for the following day to mark the end of the offensive.
On 16 May, Nasrallah said that Hezbollah had managed to expel rebel forces from Qalamoun, but that the battle for the region continued, since opposition fighters continued to be entrenched in certain areas. During the day, after reaching a "point of desperation", al-Nusra Front attacked and recaptured the Ras al-Marra border-crossing, after which it assaulted Tallat Mussa but was repelled.
On the next day, the Syrian Army and Hezbollah reportedly reached the area of al-Fakhte, on the eastern outskirts of Arsal, while rebel fighters were fortifying their positions at the Jubbah Heights, in preparation for an attack in the coming days. The Lebanese Army also shelled rebel positions near Arsal to prevent any possible attacks, after fears that retreating rebel fighters would regroup near Arsal grew, after they had withdrawn towards the outskirts of Flita and Ras al-Maara.
On 19 May, the SAA and Hezbollah captured the Flita barrens and the Flita-Arsal border-crossing, which al-Nusra Front captured the previous week. Following this advance, government troops started to prepare for the final assault on the heavily fortified Jubbah Heights. According to the Hezbollah-run Al-Manar TV, the offensive had destroyed or dismantled 40 rebel bases and four operations rooms, with only one operations room remaining near Flita. On 20 May, the Syrian Army and Hezbollah captured a number of hilltops on the southern outskirts of Flita. Some rebels retreated toward Arsal, while others fled toward Jarajeer.
On 21 May, the Army and Hezbollah advanced further, capturing additional peaks and fully besieging al-Nusra Front in a small portion of the mountains, as they were in full control of all of the border crossings in the Qalamoun region by this point and had regained 310 out of 780 square kilometers of Lebanese and Syrian territory seized by rebels. Two days later, Al-Manar reported the Army and Hezbollah had captured the Sadr al-Bustan hilltop.