Rapid Islamic State advance threatens refugee camps along Turkish border
At least 100,000 people were trapped on Friday along Syria's border with Turkey after the Islamic State group swept through rebel territory in Aleppo province, rights groups and activists said.
The shock IS advance on two rebel-held towns came as IS faced an offensive further east in its own heartland of Raqqa province.
IS fighters cut a key road between the rebel towns of Azaz, close to the Turkish border, and nearby Marea, journalist Maamoun Khateeb told AFP from Azaz.
"This is a disaster," Khateeb said, adding that some 15,000 people were now besieged in Marea.
The attack threatens tens of thousands of internally displaced Syrians living in informal camps near the border, closed by Turkey for several months.
"We are terribly concerned... about the estimated 100,000 people trapped between the Turkish border and active frontlines," said Pablo Marco, regional operations manager for Doctors Without Borders (MSF).
MSF said it was evacuating patients and staff from a hospital it supports in Salamah, a nearby town, just three kilometres from the frontline.
"There is nowhere for people to flee to as the fighting gets closer," Marco said.
Gerry Simpson from Human Rights Watch said the number of Syrians trapped along the closed border could be as high as 165,000.
Marea and Azaz both fell to opposition forces in 2012 and have been vital stops along a rebel supply route from Turkey.
IS has tried to advance on both towns for months.
In a statement on Friday, IS said it launched a "surprise attack" and seized a series of villages near Azaz.
Also on Friday, government bombardment on rebel-controlled areas of Aleppo province left at least 15 people dead, rescue workers said.
At least two people were killed in barrel bomb attacks on an opposition-controlled eastern district of Aleppo city, the civil defence - known as the White Helmets - said.
Air strikes also killed nine people in the town of Hreitan and four in Kfar Hamra.
Since fighting intensified there in 2012, Aleppo province has been transformed into a patchwork of territories held by the government, rebels, Kurds, and Islamic militants.
The IS offensive through Aleppo province came as the US-led coalition carried out at least 150 air strikes in support of an offensive near the group's northern Syria stronghold, a monitor said Friday.
The strikes are part of a twin assault on Raqqa in Syria and Fallujah in Iraq, as ground forces prepare for the most significant assaults against IS since it declared a "caliphate" straddling Iraq and Syria in 2014.