Assad Kanjo said Monday that Nusra Front fighters have been gathering in the town of Sarmada in the northern Idlib province, some 4 miles (6 kilometers) from Bab al-Hawa, an important Turkish border crossing.

If Nusra Front fighters seize the crossing, it would block an important supply line for Western-backed rebels.

Kanjo said Nusra fighters have been gathering there for days, as part of their weeklong attack on Idlib province, where they have wrested towns and villages from rebels, mostly belonging to the Western-backed “Syrian Revolutionary Front”.

The Britain-based Syrian Observatory for Human Rights also confirmed the details.

Yesterday ISIS fighters joined Nusra Front in the attack to “Revolutionaries of Syria Front” base in village of Deir Sinbul on Idlib province .cooperation between two Al-Qaeda off-shoots is for the first time since April 2013, when Abu Bakr al Baghdadi, announced the creation of the “Islamic State”.

In another incident ISIS fighters in Syria claimed on Monday they had taken control of a gas field in the central province of Homs, the second gas field seized in a week after battles with Syrian army forces.

The hardline exterimist group posted 18 photos on social media showing the Islamic State flag raised in the Jahar gas field as well as seized vehicles and weaponry, according to the SITE jihadist website monitoring service.ISIS took the larger Sha'ar gas field on Oct. 30.

ISIS in northern Syrian town on Kobani located at the border with turkey, try to capture the strategic town but local Kurdish defender Known as YPG supported by 150 new arrived Iraqi Peshmerga and us-led coalition air bombardment standing toward more than 40 days of ISIS Attacks.