By Saturday, they had taken control of "large parts" of the country's second-biggest city, Aleppo. The surprise offensive prompted the first Russian strikes on Aleppo since 2016, and saw Syria's military withdraw its troops from the city.

The rapid advance on Aleppo came just four days into a surprise rebel offensive that is the most intense escalation in years in the country’s civil war.

Syrian rebels against the country’s President Bashar Al-Assad advanced toward one of the largest cities in the country — the first time since 2016 — following a shock offensive launched by insurgents on Wednesday,