This photo provided by Nabaa Media, a Syrian opposition media outlet, shows smoke rising over buildings that were hit by Syrian government forces bombardment, in Daraa, southern Syria. Photos / AP
Syrian government forces advanced through southwestern Syria as tens of thousands of civilians fled Syrian and Russian airstrikes, piling on trucks and heading deeper into rebel-held territory.
With violence ramping up, diplomats and experts warn that the pocket could become a geopolitical tinderbox capable of destabilising neighbouring Jordan and triggering a wider conflict between Israel and Iran.
A ceasefire agreement between the US, Russia and Jordan had largely kept the peace for months while the Syrian Army concentrated on rebel-held regions closer to its capital, Damascus.
But with those conquered, Syrian President Bashar al-Assad's forces have now turned their attention to Syria's southwest, with help in recent days from Russian airstrikes.
The Syrian Observatory for Human Rights monitoring group said that forces loyal to Assad had taken control of the town of Busra al-Harir and the nearby Lajat area, prompting an exodus of families and cutting the rebels' stronghold in half.
"Warplanes and helicopters continued hovering in the skies above Daraa province," said the group's director, Rami Abdulrahman, placing the number of airstrikes in the hundreds.
Relief workers said hospitals had been targeted, too. According to the Union of Medical Care and Relief Organisations, which supports medical staff in opposition areas, an ambulance driver was killed in Busra al-Harir as he ferried patients to a clinic.
"Nothing can justify his killing," said Ghanem Tayara, the organisation's chairman. "It is beyond comprehension that after six years medical workers are still being killed with impunity."
The Trump Administration has frequently cited the southwest ceasefire, which came into force last northern summer, as evidence that Russia can make and adhere to agreements. But it remains unclear whether Moscow has the ability or willingness to impose its will on the Syrian Government and its Iranian and militia allies.
The United Nations said that at least 45,000 people have fled government advances in recent days, a figure that officials said could double as the fighting intensifies. But Jordan - already home to almost 700,000 registered Syrian refugees - said it would keep its border shut.
Local activists and a doctor described the surrounding areas as ghost towns. Much of the population has been displaced, and those left behind are hiding in basements, they said.
"This heavy bombing has caused huge destruction," said Emad, a medical worker.
As Assad declared his intention to move into the southwest and initial skirmishes began, Israel and Jordan expressed alarm, fearing the presence of Iran-backed militias along their border, as well as a possible influx of refugees.
In a call last week to Russian Foreign Minister Sergei Lavrov, the State Department said, US Secretary of State Mike Pompeo "re-emphasised the US commitment to the southwest ceasefire arrangement that was approved by President Trump and President Putin one year ago."
The fall of the strategic town of Busra Al-Harir In #Daraa has now opened the path for Syrian forces with #Russia air support to steamroll through the province, the intensity and speed of the offensive so far is telling.
And remember No deterrent No deterrent No deterrent
The statement said it was "critical for Russia and the Syrian regime to adhere to these arrangements and ensure no unilateral activity in this area."
Although southern Syria was once a key zone of US influence, the US' military and diplomatic sway has waned significantly in recent months, and Russia has emerged as a key power broker. Rebel groups once backed by Washington said last week that they have been told not to expect American military assistance.
A spokesman for Russia's Defence Ministry blamed Syria's rebels for the worsening humanitarian situation, "despite the efforts being undertaken" by Moscow. Russian broadcaster RT reported that the country's deputy foreign minister, Mikhail Bogdanov, would meet Jordanian officials in Moscow to discuss the crisis.
King Abdullah of Jordan is in Washington this week and is expected to discuss the fate of Syria's south with American officials.
The Regime and Russian attack upon #Daraa is in its sixth day. The city has suffered enormously due to non-stop artillery raids. Today, alone, 5 civilians were killed until now. #WhiteHelmet teams are on the scene putting in exhaustive hours of rescue in the aftermath. pic.twitter.com/bHEQskQFxa
#Daraa Map shows the develpment of today 6/25 events.The regime has advanced in many fronts with non stop support from the #Russian airforce mainly destroying the hospitals and the main roads. Few min ago,#Israel striked #iranin postions/cargos in #damascus airport. pic.twitter.com/xso4ICzwzH