On 12 October, the Sunni Islamist group Hay'at Tahrir al-Sham (HTS) joined the fighting on the side of the Hamza Division, entering the Afrin region.

On 7 October, gunmen shot and killed media activist Muhammad Abdul Latif, also known as Abu Ghannoum, and his wife in the city of al-Bab.

The Third Legion, led by the Levant Front, found on 10 October that a group of Hamza Division fighters was responsible for the killing, sparking the clashes.

The next day, additional groups joined the fighting, including Hayat Tahrir al-Sham, the Sultan Suleiman Shah Division (al-Amshat), and Ahrar al-Sham on the side of the Hamza Division,[1] and the Liberation and Construction Movement[3] and remnants of the Nour al-Din al-Zenki Movement on the side of the Third Legion.

[18] Protests and demonstrations were held across multiple opposition controlled towns in northern Syria, including Mare', Al-Bab, Azaz and Kaljibrin, against the entry of HTS to the region.