Thousands of fighters and their families departed neighbouring Harasta by bus on Friday after a deal with the government to surrender the town. Insurgents in several other towns nearby have agreed to leave on similar terms.
Some army soldiers and other people captured and held by the rebels were freed on Saturday as part of the same deal and were shown on state television leaving Harasta in a minibus.
Buses queued at a crossing point and moved into the enclave along a road on the former front lines that had been cleared of barricades, debris and unexploded ordnance. They are to carry thousands more people - fighters and civilians - into exile.
The army was advancing into towns the rebels had retreated from in preparation for their exit, state media said.
It means only Douma is left of the opposition’s eastern Ghouta enclave which a month ago the United Nations said was home to 400,000 people and constituted the rebels’ main stronghold near Damascus.
The army offensive to capture it, heralded by one of the heaviest bombardments in the seven-year war with warplanes, helicopters and artillery, has killed more than 1,600 people, said the Syrian Observatory for Human Rights, a war monitor.
Residents and rights groups have accused the government of using weapons that kill indiscriminately - inaccurate barrel bombs dropped from helicopters, chlorine gas and incendiary material that sets raging fires.
Syrian President Bashar al-Assad and his close ally Russia, which has helped his air campaign, have denied using all those weapons and say their offensive was needed to end the rule of Islamist militants over civilians.
About 7,000 fighters, along with family members and other civilians who do not wish to come back under Assad’s rule, were to leave the towns of Zamalka, Arbin, Ein Terma and Jobar starting on Saturday, rebels and state media said.
They will go to Idlib province in the northwest - the destination for many such “evacuations” after sieges and ground offensives forced numerous rebel enclaves to surrender in the past two years.
It will not mean an end to their experience of war. Syrian military and Russian air raids on Idlib have increased in the past week, killing dozens of people.
Idlib is also unsettled by fighting between the rebel groups. On Saturday, an explosion at a headquarters for al Qaeda’s former affiliate killed at least seven people and injured 25 others.
The rebels leaving the eastern Ghouta towns will release several thousand captured Syrian soldiers, state media reported. The Britain-based Observatory said there were also negotiations with the Jaish al-Islam rebel group that controls Douma to release prisoners.
Russia will guarantee that civilians who remain in the areas recaptured by Assad will not be prosecuted, rebels said on Friday. However, rights groups have said some men were forcibly conscripted after fleeing the fighting.
A Russian military webcam at the al-Wafideen crossing point near Douma showed small groups of civilians continuing to flee the danger of further bombardment into government territory on Saturday, carrying children and sacks of belongings.
Russia’s military said on Saturday more than 105,000 people had left eastern Ghouta, including over 700 on Saturday.
Tens of thousands have fled their homes in the past week as the bombardment of Douma intensified and refugees from other parts of Ghouta found the basement bomb shelters already too full to take them.