The Islamic State is digging a moat around its biggest stronghold in Iraq, Mosul, in preparation for an expected attack from the Iraqi army and its U.S. partners, and is using oil tankers to construct a wall around the city, which it would set on fire if the Iraqi army gets too close, according to Mosul residents.

The organization is also digging tunnels underneath the city as a means of stopping the army’s advance, shutting down some neighborhoods, and setting bombs. The attack on the city, which ISIS captured two years ago, is planned for next month. It would mark a major turning point in the fight with ISIS, after the Iraqi army regained control of some key ex-ISIS territories.

Al Jazeera quoted the chairman of the Joint Chiefs of Staff in the Iraqi-U.S. coalition general Joe Dunford that “We assess today that the Iraqis will have in early October all the forces marshalled, trained, fielded, equipped that are necessary for operations in Mosul.”

An Iraqi army official told media that suicide attacks are also possible during the push into Mosul, adding that ISIS are prepared to fight to the last man in order to keep control over Mosul and that the preparations they are making will make the clash “challenging”. Besides challenging, it’s likely to take its toll on the civilian population of Mosul, which was around two million people at the time ISIS took over.

Recently, parts of a Mosul university student’s diary were released by the BBC, offering a rare glimpse into the everyday life of people in Mosul after ISIS took over.

Earlier this week the Iraqi forces launched an attack on a Shirqat, another northern Iraqi city held by the Islamic State, which is seen as an important stepping stone before the attack on Mosul. So far, the army has regained control over 12 villages around Shirqat and is advancing towards the center of the city.

By Irina Slav for Oilprice.com

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