Some 300 Islamic State fighters remain in the small patch of territory still controlled by the terror group in Mosul’s Old City, a senior Iraqi commander has said.

Lieutenant General Sami al-Aridi, of Iraq’s special forces, told the Associated Press that the militants’ hold on Mosul has shrunk to an area of 600 square yards.

A large number of civilians are believed to be trapped in the IS-run enclave, with around 1,500 fleeing with every 100-yard advance by Iraqi forces.

Iraqi forces moved to besiege the Old City before launching their attack in order to prevent IS fighters from fleeing to neighbouring Syria, but Lt Gen al-Aridi said hundreds of militants still managed to escape from the Old City alone.

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“They just shave their beards and walk out,” he said. “Just yesterday we captured two among a group of women and children.”

Late on Tuesday, Iraq’s Prime Minister Haider al-Abadi congratulated the armed forces on a “big victory” in Mosul, despite ongoing clashes. He declared an end to the extremist group’s self-styled Islamic caliphate in June.

IS captured Mosul in a matter of days when it swept across northern and central Iraq in the summer of 2014. Iraqi forces backed by a US-led coalition launched a major operation to retake the city in October.