It took an international coalition nine months to liberate Iraq's second largest city Mosul from the so-called Islamic State. The city had become the de facto capital of the militant group, after the ISIL leader declared the founding of its caliphate state there. For those that fought on the ground, the experience may never be forgotten. Our reporter Xinri Fu has this.

Major Moussawi is an officer serving the Baghdad fast reaction unit, which has been fighting Islamic State for a long time. The battle of Mosul was one of the most significant efforts he has been in.

MAJOR GHASSAN AL-MOUSSAWI IRAQI OFFICER INVOLVED IN MOSUL LIBERATION "The battle for Mosul was more important than others because ISIL was trapped in the area, which was called the core of terrorism. That was also where the so-called 'state' was established."

Beginning in October 2016, Iraqi forces and Islamic State were engaged in close fight that would last for over 9 months. Major Moussawi witnessed what the terrorists did to the residents, and he was deeply shocked.

MAJOR GHASSAN AL-MOUSSAWI IRAQI OFFICER INVOLVED IN MOSUL LIBERATION "They used dirty methods. They used children, women, elderly people, and other citizens as human shields."

The buildings in Mosul were very close to each other with complicated layouts, which inevitably led to alley combat. Iraqi forces tried their best to protect civilians and rescue them from the Islamic State, and that made the battle even harder. Many residents were confused and some believed the Iraqi forces would kill them along with the terrorists. So they were afraid of contacting the army. Moussawi says, he and his fellow soldiers worked to combat this rumor with their friendly acts.

MAJOR GHASSAN AL-MOUSSAWI IRAQI OFFICER INVOLVED IN MOSUL LIBERATION "When the civilians got in touch with us, we hugged them and secured their houses. News of this spread among the people of Mosul. Even those in the areas that had not yet been liberated knew about this, that the army was not as the Islamic State had described. They learnt that we are people who embrace and protect."

Major Moussawi said changing the minds of the embattled people of Mosul was an epiphany for him. He knew at that moment that the final victory of the war was just a matter of time. When the army proceeded to IS's last fortresses, some residents even risked their lives to provide information and assistance for them to drive the terrorists away.

MAJOR GHASSAN AL-MOUSSAWI IRAQI OFFICER INVOLVED IN MOSUL LIBERATION "The feeling of victory was like a father finding his lost son. We recovered this land and the people were there to welcome us. They were all good and safe. I cannot describe this moment in words."

One year on from declared victory, Moussawi still continues his fight against the militant groups in his country. He's now in Iraq's deserts, inspecting and clearing sleeper cells of the Islamic State group. He wants to finish off the terrorists, once and for all.

MAJOR GHASSAN AL-MOUSSAWI IRAQI OFFICER INVOLVED IN MOSUL LIBERATION "There might still be the residue of Islamic State, but their physical presence in Iraq is over. What's left now are only a few sleeper cells, which are fully under control and will be wiped out.