The Iraqi army and Kurdish forces, backed by US-led coalition air strikes, have begun the long-awaited battle to retake the city of Mosul from Isis' hands, Iraq's Prime Minister Haider al-Abadi has said.
Convoys of troops began mobilising east of the city early on Monday morning. Air strikes send huge plumes of smoke into the air and artillery fire could be heard.
Mosul, which is regarded as Isis’ “second city”, is the last major stronghold of the jihadist group in Iraq. It has been under Isis' control since June 2014, but a US-backed Iraqi offensive to retake the city has been planned for months.
The military operation is the most complex carried out in Iraq since US forces withdrew from the country in 2011.
In an address on state television, Mr Abadi said: “The time of victory has come and operations to liberate Mosul have started.”
“Today I declare the start of these victorious operations to free you from the violence and terrorism of Daesh,” he said, using another term for the jihadist group.
US and French forces had already begun bombing Isis targets in Mosul ahead of the offensive.
Isis fighters are said to be dug in and preparing to battle hard to maintain control, with suicide bombers, car bombs, and booby traps on major roads. Unconfirmed reports said that residents in the city have begun fighting back against Isis, stealing weapons and burning militant vehicles.
Ahead of the battle, the Iraqi army dropped tens of thousands of leaflets over Mosul urging residents to hide before the offensive begins.
The leaflets carried several messages to the citizens of the northern attempting to reassure them that the advancing army “would not target civilians” but warned them to avoid the known locations of Isis militants.
"Keep calm and tell your children that it is only a game or thunder before the rain," a leaflet said. "Women should not scream or shout, to preserve the children's spirit."
"If you see an army unit, stay at least 25 metres away and avoid any sudden movements," another said.
They have previously forced civilians to remain where they are rather than flee during previous battles to maintain territory.
The announcement of the Mosul offensive comes just hours after Isis lost control of the symbolically important town of Dabiq in Syria to a group of rebels after a short battle.
The opposition fighters were able to retake the town with “minimal” resistance despite Isis prophecies that Dabiq was to be the scene of an apocalyptic final battle between Muslims and Christians.
Isis has lost a third of its territory in Iraq and Syria in the past year as counter insurgent forces and Western coalition air strikes push the group back.
Last week, the UN warned that it was bracing itself for the world’s biggest and most complex humanitarian effort following the battle which it expects to displace up to one million people and see civilians used as human shields.
Camps have been prepared on the outskirts of Isis territory to cope with the movement of people.
The Iraqi government launched a radio station to help Mosul residents stay safe during the offensive last month broadcasting from Qayyara, a town around 40 miles south of the city.
On Sunday, the Iraqi Prime Minister Haider al-Abadi confirmed that Shia militants would not enter the heavily Sunni city.
Previously local Sunni politicians and regional Sunni-majority states including Turkey and Saudi Arabia had warned that Shia soldiers taking part could lead to sectarian fighting.
At least 1,500 Turkish-trained Sunni militia men will take part in the Mosul offensive, it emerged on Monday, after initial resistance from Baghdad.
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