While the world is fixated on ISIS, al-Nusra Front continues to conquer new territory in Syria.

Beirut (AFP) – Al-Qaeda’s Syrian affiliate and its allies seized the last regime-held military base in northwestern Idlib province on Wednesday, in the latest setback for President Bashar al-Assad’s forces.

Al-Nusra Front and a coalition of mostly Islamist groups captured the Abu Duhur military airport after a siege that lasted two years, the Syrian Observatory for Human Rights monitor said.

“After a violent attack that had been taking place since Monday, Al-Nusra Front and some Islamist factions control all of the Abu Duhur military airport,” the Britain-based Observatory said.

The attacking force began to enter the base on Tuesday night.

Observatory chief Rami Abdel Rahman said the forces appeared to have taken advantage of a massive sandstorm that blanketed much of the Middle East and made it difficult for regime aircraft to carry out strikes.

“The army is no longer present in Idlib province,” he added, saying that the soldiers who had been defending the base withdrew towards Aleppo province in the east.