Syrian rebels appealed for international assistance to counter a new offensive by Isis (Islamic State) in the northern province of Aleppo that could reshape the battlefield in Syria.
The surprise assault opened a new front in the multipronged war waged by the extremist group across Iraq and Syria, and underscored Isis' capacity to catch its enemies off guard.
The push took the militants within reach of the strategically vital town of Azaz on the Turkish border.
Rebel groups rushed reinforcements to farmland north of Aleppo after Isis seized five villages.
Videos posted on social media accounts allied with Isis showed the group controlling checkpoints in the small town of Sawran.
Azaz controls access to one of the most important border crossings between Syria and Turkey. If the town were to fall, supply lines for rebel forces in Aleppo city would be cut and their presence in the province jeopardised, rebel commanders said.
"Automatically [Isis] would gain control of Aleppo city," said Abu Mohammed, a leader of the rebel group Thuwar al-Sham based in the Turkish town of Gaziantep, who uses a nom de guerre.
If Isis seized the area, it would also extend its reach along the Turkish border, amplifying its capacity to secure supplies and smuggle in foreign fighters.
Any US intervention on behalf of rebels in the area would be complicated by the presence of al-Qaeda-affiliated Jabhat al-Nusra alongside more moderate rebel groups. The rebels have asked the international coalition to carry out strikes and have presented co-ordinates of Isis positions, "but so far we have heard nothing," Abu Mohammed said.
- Washington Post-Bloomberg