The sources said that the first group of Al-Nusra terrorists, allied groups and their family members left al-Qadam region in Southern Damascus for Idlib in an agreement with the army.
They said that 600 militants and their family members will leave al-Qadam in the first phase of evacuation.
The total number of terrorists and their family members in al-Qadam stands at 2,000.
The militant who do not want to leave al-Qadam for Idlib are to hand over their arms and ammunition and will apply for government amnesty.
Militant-affiliated websites disclosed on Sunday that gunmen of the Free Syrian Army (FSA) and Tahrir al-Sham Hay'at (the Levant Liberation Board or the Al-Nusra Front) agreed on withdrawal of their gunmen from al-Qadam to militant-held regions in Idlib province.
They further reported that the army had previously given a 48 hours ultimatum to the militants to leave al-Qadam.
In the meantime, military analysts said that the army's rapid advances in Eastern Ghouta have forced the FSA and Tahrir al-Sham Hay'at to agree withdrawal from their positions in al-Qadam.