The fatwa
The Supreme Military Council of the Army of Conquest which controls East Aleppo has published the following fatwa -

Declaration to the patient citizens of Aleppo
Those people who attempted to escape without paying were shot.

In fact, no family is able to collect the necessary sum to free their children and old people after such a long period of occupation, during which food was sold to them by the jihadists at exorbitant prices.

The Supreme Military Council of the Army of Conquest is under the command of the Supreme Judge of the Tribunal of the Charia, the Saudi cheikh Abdullah al-Muhaysini. This person has declared his allegiance to al-Qaïda. In an interview broadcast on 28 October, he declared that the combatants present in Syria are foreigners supported by a few Syrian collaborators, and he reproached the Syrians for refusing to participate in the jihad.

The Army of Conquest is a coalition of several armed groups around the al-Nusra Front (in other words, al-Qaïda in Syria) which became the Syrian Liberation Front (Fatah al-Cham).