Dozens killed in Ghouta airstrikes as thousands flee
The strikes were carried out by Russian warplanes and hit the Saqba and Kfar Batna areas.
The Syrian regime now controls 70 percent of Eastern Ghouta and have split the remaining rebel-held territory into three shrinking pockets.
Regime forces captured Hammourieh on Thursday, one of Eastern Ghouta's towns. Nearly 20,000 civilians fled the town and surrounding areas in the first mass exodus since the Ghouta offensive began a month ago.
More than 1,200 have been killed in airstrikes and rocket fire to date, according to agencies.
UNICEF has put in place an emergency response plan to cope with up to 50,000 people fleeing Eastern Ghouta, spokeswoman Marixie Mercado told a UN briefing on Friday.
"We have been working, planning to respond to evacuations for a while and specifically to provide shelters with emergency assistance," she said.
The regime’s overnight advance into Hammourieh opened up a corridor into regime-held areas for those looking to escape the town.
State-run Al-Ihkbariya said civilians would be taken to a center for identification and relief.
The UN is trying to determine the numbers fleeing Eastern Ghouta, but has been unable to observe the evacuations.
Deputy UN spokesman Farhan Aziz Haq said they were trying to assess the needs of shelters, including the Dwier collective centre manned by Syrian Arab Red Crescent workers.
The World Health Organisation is sending medical equipment and hospital beds to the Dwier centre.
The exodus could mark a turning point in Eastern Ghouta, one of the Syrian war's largest battles to date, in which the fate of civilians in the enclave has been central.
Both Ghouta and Afrin underscore the intractability of the Syrian civil war, which is entering its eight year.
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Agencies contributed to this report.