Syrian rebel fighters have said they launched an attack on Taftanaz military airport in the northern province of Idlib, cutting off Syria's biggest city Aleppo from the capital Damascus.
The Syrian government has used Taftanaz to fuel helicopter gunships and fighter jets that have bombarded nearby villages. The incident comes a day before an opposition conference begins in Qatar.
This is the start of one of their more concentrated attacks on Syrian military power, according to rebels.
Syrian rebels launched a dawn offensive to take control of a key airbase in the country's north, activists have said.