UN says 8,400 housing sites were 'severely damaged or completely destroyed' in the battle to retake the city from ISIL.

Iraqi Prime Minister Haider al-Abadi formally declared victory over the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) on July 10.

While the victory is a significant blow to ISIL, the cost of the nearly nine-month battle to retake the city has been enormous with almost a million people forced to flee, thousands killed, and much of the city reduced to rubble.

In its latest damage assessment on July 8, UN Habitat estimated that more than 8,400 housing units had been destroyed or severely damaged. In the Old City alone, more than 5,390 housing sites were destroyed or severely damaged.

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At the time of the final push to retake the city in early July, a senior UN official estimated the cost to rebuild the city would be more than $1bn.

Iraqi forces took the eastern side of Mosul from ISIL in January after 100 days of fighting and started attacking the western side in February. In April, the United Nations said the damage to houses were two-and-a-half times greater than in the eastern districts.

Source: Al Jazeera