The East Aleppo offensive (2017), also referred to as the Dayr Hafir offensive, was an operation launched by the Syrian Army to prevent Turkish-backed rebel forces from advancing deeper into Syria, and also to ultimately capture the ISIL stronghold of Dayr Hafir. Another aim of the operation was to gain control of the water source for Aleppo city, at the Khafsa Water Treatment Plant, in addition to capturing the Jirah Military Airbase. At the same time, the Turkish-backed rebel groups turned towards the east and started launching attacks against the Syrian Democratic Forces, west of Manbij.
Offensive
Syrian Army push to al-Bab
On 17 January, the Syrian Army launched an assault led by its Tiger Forces, capturing a village to the south of al-Bab. The SAA captured four more villages to the south of the city within the next three days, and another 13 villages to the southwest of al-Bab between 21 and 24 January. By 29 January, 20 villages had come under Army control.
On 1 February, the Turkish-backed rebels captured two villages to the southwest of al-Bab, cutting the main road between the city and Aleppo from another side in front of the recent advances by pro-Syrian government forces who had come within . Meanwhile, the SAA also captured a village to the south of the Kuweires airbase.
By 5 February, the SAA was within two kilometers of cutting the last road into al-Bab, with support from Hezbollah and Russian artillery. The next day, they captured Tal Uwayshiya hill, which overlooks the main supply route to al-Bab. The SAA advance effectively cut off the last main supply route to the city, putting it under a siege. Government advances continued on 7 February, with SAA and Hezbollah capturing three villages and a nearby hill to the south of Al-Bab. They later captured a hill and many other sites to the south of the Kuweires airbase, extending their control over Sabkhat al-Jabbul and fully securing the road near it. Later on the same day, it was reported that the rapid Syrian Army advances had nearly encircled 5,000 ISIL militants within Al-Bab and its environs.
During the night of 7 February, Turkish forces and rebels launched an assault at Al-Bab, capturing several strategic hills and breaking into the city. On 9 February, the Syrian Army was within of al-Bab. On the same day, the rebels clashed with the Syrian Army for the first time near al-Bab, in a village to the southwest of the city.
Syrian Army advance east of al-Bab
After the Syrian Army advanced within of the city of al-Bab on 10 February, the next day, it was reported that Turkish-backed rebel forces had captured a strategic roundabout, effectively cutting off the Syrian Army from Al-Bab. To prevent further southern advances by the rebels, the military started operations east of Kuweires Airbase into ISIL territory so to cut off the rebels.
Between 12 and 16 February, the Syrian Army captured nine villages northeast of the airbase, advancing some four kilometres and coming within five kilometres of the ISIL-held town of Dayr Hafir.
Between 21 and 25 February, the military seized a dozen more villages and imposed artillery fire-control over Dayr Hafir. The Army started bypassing Dayr Hafir in an attempt to encircle it and force ISIL forces to withdraw instead of launching a direct assault on the town due to the possibility of extensive ISIL fortifications.
On 25 February, amid a large retreat of ISIL forces from rural areas of east Aleppo, and following the fall of Al-Bab to Turkish-backed rebel forces, it was reported that most of ISIL's fighters had withdrawn from the town of Tadef. At this point, it remained unclear whether the town would be taken over by pro-government or rebel fighters. The next day, the Syrian Army entered Tadef and took control of the town. Subsequently, clashes erupted near Tadef between the Army and Turkish-backed rebels. The rebels claimed that at least 22 Syrian soldiers were killed in the fighting, while at least six rebels also died. Still, despite this, the military continued with its advances, seizing another two villages.