Nearly 20,000 civilians fled Eastern Ghouta on Thursday as Syrian government troops entered a key town in the rebel enclave near Damascus.
"Regime forces assaulted Hammuriyeh and were able to control parts of it", in the south of the enclave, the Syrian Observatory for Human Rights said.
Residents – most of them women and children – fled on foot, in cars and on motorcycles via the town of Hammuriyeh, where the Syrian army had opened a corridor, reported AFP. They reached a government-held checkpoint in Adra.
According to the UK-based Observatory at least nearly 20,000 civilians fled Eastern Ghouta on Thursday. It was the first major exodus from the territory after nearly four weeks of intense bombardment by government forces and Russia and came as the Syrian civil war entered its eighth year.
Meanwhile, the International Committee of the Red Cross said that a new convoy carrying food aid entered the rebel enclave on Thursday and was headed to Douma – the largest town in Ghouta.
Thursday's convoy of 25 trucks was carrying food parcels and flour bags for more than 26,000 people.
"This is just a little of what these families need," the ICRC said.
It was the third delivery of aid to reach Douma in 10 days. Aid deliveries, carried out jointly by the ICRC, Syrian Arab Red Crescent, and the United Nations, need permission from all warring sides in Ghouta.
On February 18, forces loyal to Syrian President Bashar Al Assad – backed by Russian air support – launched an assault on eastern Ghouta, which is the last opposition bastion outside the capital, Damascus.
Syrian troops have seized more than 60 per cent of Ghouta since the offensive, which split the enclave into three sections, each controlled by different rebels. The area around Hammuriyeh is controlled by the Faylaq Al Rahman faction.
More than 1,220 civilians – a fifth of them children – have been killed since the launch of the offensive.
Moscow said on Thursday that it was committed to helping the Assad government “finish off” rebels in eastern Ghouta.
Russia has provided few details of its involvement in the offensive on Ghouta but Foreign Minister Sergei Lavrov on Thursday left no doubt Moscow's forces were taking an active part.
"We will continue fighting terrorists, we will finish them off, we will help finish them off in Eastern Ghouta, where the Syrian army is now conducting operations with our support," he said.
Meanwhile, Turkish-backed forces launched a bombardment of Syria's Kurdish-held Afrin and closed in on the main city, in an offensive that could redraw the map in northern Syria.
Turkish Foreign Minister Mevlut Cavusoglu's spokesman said on Thursday that Mr Cavusoglu's planned visit to Washington on March 19 has been postponed. He did not give a reason for the decision.
The announcement follows US President Donald Trump's call to replace Rex Tillerson as secretary of state.
Turkey has been angered by Washington's support for the Syrian Kurdish YPG militia in the fight against ISIL. Turkey sees the YPG as a terrorist group and an extension of the outlawed Kurdistan Workers’ Party (PKK).
On Thursday, Ankara said it would flush out the Kurdish militia from the centre of Afrin “in a very short time”, as pro-Turkey forces surrounded the city.
"The circle is closing in around the terrorists. We anticipate that the centre of Afrin will be cleared of terrorists in a very short time, God willing in the coming days," Turkish presidential spokesman Ibrahim Kalin said.
Kalin told state broadcaster TRT in an interview that the offensive, dubbed operation Olive Branch, had secured 70 per cent of the territory of Afrin district.
International efforts have consistently failed to stop the seven-year war in Syria, with more than 500,000 people killed since the conflict first erupted, and more than half of Syria's pre-war population of 20 million displaced.