(London Telegraph) Set amid the rolling plains outside Aleppo, the town of al-Safira looks just like another vicious battleground in Syria's civil war. On one side are lightly-armed rebels, on the other are government troops, and in between is a hotly-contested no-man's land of bombed-out homes and burned-out military vehicles.
The fight for al-Safira is no ordinary turf war, however, and the prize can be found behind the perimeter walls of the heavily-guarded military base on the edge of town. Inside what looks like a drab industrial estate is one of Syria's main facilities for producing chemical weapons - and among its products is sarin, the lethal nerve gas that the regime is now feared to be deploying in its bid to cling to power.
Last week, Washington said for the first time that it had evidence of Sarin being used in "small" amounts during combat operations in Syria, a move that President Barack Obama has long warned is a "red line" that President Bashar al-Assad must not cross.
Advertisement - story continues below
But as the West now ponders its response, the fear is not just that President Assad might start using his chemical arsenal in much greater quantities. Of equal concern is the prospect of it falling into even less benign hands - a risk that the stand-off at al Safira illustrates clearly.