The rebel coalition led by the "Hayat Tahrir al-Sham" group unexpectedly attacked government positions, capturing Aleppo - Syria's second-largest city.
According to the BBC, a new wave of violence was triggered by this assault. It all began on November 27, when the rebels launched an offensive in Aleppo province, seizing a military base and several villages, thereby blocking an important highway. Within a few days, they had entered Aleppo, and by Sunday, the city’s citadel, which had been a key stronghold for government forces for decades, was under their control. The rebels even released photographs from the city showing the ancient fortress that Bashar al-Assad’s government failed to hold.
By this time, the conflict in Syria had somewhat quieted down, although it had been raging since 2011, evolving from peaceful protests into fierce battles between government troops and various rebel factions. The war involved not only Syrians but also international forces: Russia, Turkey, Iran, the USA, and others.
Thanks to support from Russia, Assad’s regime regained control over most of the country by 2020. However, regions in the north and northwest, including Aleppo, remained under the control of different rebel groups, with HTS being the most influential. Yet, changes occurred even here. After several years of cooperation with other opposition groups, HTS prepared a new offensive, taking advantage of the weakening of government forces amid an internal political and military crisis in Syria.
In addition to shifts in the balance of power within Syria, the situation was influenced by events in Lebanon and Iran, as well as Russia's war in Ukraine, which reduced its ability to actively support Assad. Moreover, assistance to the Syrian government is limited by Israeli strikes on Iranian military sites.
Source: BBC.