Air strikes by the Syrian regime on Sunday killed 14 civilians in the last major opposition bastion of Idlib in the country's north-west, a war monitor said.
Government forces and their allies have increased their deadly bombardment of the militant-dominated region in recent weeks, chipping at its southern edge and causing tens of thousands to flee their homes.
Eight of those killed Sunday died in a regime barrel bomb attack in the town of Sarmeen. Seven of them were from the same family, the Syrian Observatory for Human Rights said.
Rescue workers pulled the bodies of a girl, 9, and a boy, 13, from the debris of a two-storey building.
Their father, Abu Fida, stood by weeping.
"It's a terrible disaster," he said.
Abu Fida said he and his family had fled bombardment on Sarmeen on Thursday, with just the clothes on their backs.
They returned on Saturday night to collect their belongings and decided to spend a last night at home before leaving for good.
"I wanted to get my family out this morning but my wife told me to go to work," Abu Fida said. "So I sent them a driver with a car to transport their things," but then the bombs hit the house.
His wife was inside the house when it was struck, but he survived with three other children.
In the rest of the embattled bastion on Sunday, regime air strikes killed another six civilians, the Observatory said.
Nine years into the war, the Damascus regime is back in control of about 70 per cent of the country, but the region of Idlib remains beyond its reach.
Syria's former Al Qaeda affiliate controls the Idlib region, home to about three million people, but pro-Ankara rebel groups are also present.
In recent months, regime and allied forces have pressed northwards along the M5 motorway that connects the capital Damascus to second city Aleppo in the north, crossing Idlib.
Last week government forces retook from rebels the key town of Maaret Al Numan along the motorway and are now just several kilometres from the abandoned town of Saraqeb.
Clashes are also raging in the bastion's eastern flank in Aleppo province, where state news agency Sana said four television journalists were wounded on Sunday.
The journalists for a pro-Damascus channel and two Arabic-language Iranian outlets were targeted by "terrorists", Sana said.
A Turkish-Russian deal in 2018 saw Turkish station troops at observation posts around Idlib, but the agreement has failed to stem repeated regime military offensives.
On Sunday morning, the Observatory said a Turkish military convoy of hundreds of vehicles entered northern Syria, and took up position in Idlib and neighbouring Aleppo province.
Increased violence since early December has forced around 388,000 people to escape their homes in north-western Syria, the UN says.
The Observatory says more than 260 civilians have been killed.
Half of the Idlib region's residents have been displaced throughout the war, with many living in precarious shelters in the countryside along the Turkish border.
Ankara, which already hosts more than three million Syrian refugees, fears the latest fighting will lead to another mass influx.
On Sunday, hundreds of Syrian men, women and children marched towards the frontier demanding to be allowed through in a symbolic protest.
Near the Syrian border town of Harem, women lugged bags and men carried small children towards the razor-wired wall blocking the way to Turkey.
"From Idlib to Berlin," read one banner, referring to the German capital many Syrians dream of reaching as they escape the war.
Among the demonstrators, Mohammed said he was looking to a better alternative for his family of nine after fleeing his hometown.
"Our goal is to go and live in a safe country, Turkey or Europe," he said. "Here, it's no longer safe."
Syria's civil war has killed more than 380,000 people since it started in 2011 with the brutal repression of anti-government protests.