Female Kurdish YPG fighter gestures during fighting with ISIS in Syria (file)
Female Kurdish YPG fighter gestures during fighting with ISIS in Syria (file)Reuters

Kurdish forces backed by Arab rebel groups captured a strategic air base and the adjacent town in northern Syria from rival anti-government factions overnight, a monitoring group said early Thursday.

The Kurdish People's Protection Units (YPG) and its Arab allies expelled Islamist and other rebel fighters from the Minnigh air base and adjacent town, north of Syria's second city Aleppo, the Syrian Observatory for Human Rights told AFP.

The advance comes after days of fierce clashes that saw YPG forces advance east from the Kurdish stronghold of Afrin and take over a series of villages before reaching Minnigh.

"With the defeat at Minnigh, Islamist fighters lost the only military airport they held in Aleppo province," Observatory head Rami Abdel Rahman said.  

Government forces lost control of the Minnigh airport in August 2013, two years after the uprising in Syria first erupted.

Rebel groups are facing a dual advance by both Kurdish forces coming from the west and regime troops - backed by a barrage of Russian air strikes - pressing an offensive north from Aleppo city.

More than 500 people have been killed since the government began its assault on February 1, the Observatory said Wednesday.

YPG forces regularly clash with Islamist and jihadist fighters in northern Syria, but its most active front is further east against the Islamic State (ISIS) extremist group.

AFP contributed this report.