The Islamic State (Isis) governor of the besieged city of Manbij has reportedly been killed in Syrian Democratic Forces (SDF) shelling as the city's last supply route was cut off,. High-ranking commander Osama al-Tounsi is one of 400 militants who have been killed by the US-backed SDF since the beginning of the ongoing military operation aimed at liberating the northern Syrian city from Daesh (Isis).

On Friday 10 June US-backed forces took control of the last route into the city, in Aleppo province, completing their encirclement of Manbij. The assault comes as IS-held Fallujah comes under pressure in neighbouring Iraq and also in Sirte, Libya, which is set to fall to forces loyal to Libya's unity government.

The Kurdish-led Syrian Democratic Forces (SDF) are an umbrella coalition consisting of Kurdish People's Protection Units (YPG) with Arab, Christian and Turkmen militias. They targeted an IS convoy trying to escape Manbij which killed 10 IS jihadists in shelling, including governor al-Tounsi.

The Manbij operation, launched on 31 May, SDF and allied Manbij Military Council have recaptured an estimated 90 villages and farms in the area surrounding the city. Al-Tounsi's convoy, which was said to consist of three cars, was exiting to the west towards IS-controlled al-Bab city when the SDF heard of his escape and bombed them.

"Al-Tounsi was trying to escape Manbij along with his family and a number of his escorts. Their convoy was hit with several artillery shells. They were all killed in the attack," local media activist Nasir Taljbini told ARA News.

"Our forces have also cut off all roads linking Manbij with other Syrian cities, imposing a complete siege on ISIS inside the city after retaking the Manbij-Aleppo road," SDF official Habun Osman told ARA News.

In the past week the SDF cut off IS supply lines between Manbij and the cities of Raqqa and Jarablus. The extremists have been using the Manbij border strip as a key entry point for foreign fighters to Turkey with the passage is said to be the last remaining channel on the border.

So far at least 20 SDF fighters have been killed in fighting near the city, including prominent commander Abu Layla, with more than 100 have been wounded. Thirty civilians has also lost their lives.

Fighting ISIS
A fighter of the Syria Democratic Forces mans an anti-aircraft weapon in the southern rural area of Manbij, in Aleppo Governorate, Syria Rodi Said/ Reuters