This marks an epic milestone for the Iraqi security forces, who had crumbled in the face of an IS onslaught across Iraqi in 2014.

Baghdad: Key dates in the offensive against the Islamic State group in Iraq's northern city of Mosul where on Sunday Prime Minister Haider al-Abadi declared victory.

- The battle begins -

- October 17, 2016: Iraqi forces launch the assault to recapture Iraq's second city, conquered by IS in June 2014. A month later jihadist group's supremo Abu Bakr al-Baghdadi made his only public appearance in Mosul, to urge Muslims worldwide to move to the recently proclaimed "caliphate" straddling Iraq and Syria.

Tens of thousands of army, police and counter-terrorism troops are thrown into the long-awaited offensive with crucial support from a US-led coalition.

In two weeks dozens of surrounding localities are recaptured, including the Christian town of Qaraqosh around 15 km from Mosul.

- Entering Mosul -

- November 1: The army says it has entered Mosul city for the first time since 2014.

- November 3: Baghdadi breaks a year-long silence, urging followers to fight to the death for Mosul.

- November 8: Iraqi Kurdish peshmerga fighters say they have reached Bashiqa, a dozen kilometres north of Mosul.

- November 13: Iraq says it has recaptured Nimrud, an ancient city southeast of Mosul.

- November 23: Shia-dominated paramilitary units known as the Hashed al-Shaabi say they have cut IS supply lines between Mosul and the jihadists' Syrian stronghold Raqa, 400 km to the west.

The Iraqi forces face strong resistance from the jihadists who carry out numerous suicide attacks.

- East Mosul retaken -

- December 29: Government troops end a two-week pause and launch the second phase of their assault on east Mosul.

- January 8: Iraqi units reach the Tigris River that divides Mosul and take up positions near one of the city's five bridges, all now destroyed.

- January 24: The Joint Operations Command coordinating the fight says the east has been "fully liberated".

- Battle for west begins -

- February 19: Mr. Abadi announces the start of the battle for west Mosul, with Iraqi forces backed by coalition air power and support from coalition advisers.

- February 24: Iraqi forces seize full control of Mosul airport and enter their first west Mosul neighbourhood.

- March 12: A US envoy says Iraqi troops have cut all roads into western Mosul, trapping remaining IS fighters inside.

- March 14: Iraqi forces say they have captured the city's train station after reaching other symbolic sites such as the regional government headquarters and the city's museum.

- Old City -

May 4: Iraqi forces launch a second front in northwestern Mosul to further seal the siege on the Old City. Aid groups say jihadists are holding tens of thousands of civilians as human shields.

May 16: A military spokesman says almost 90 percent of west Mosul has been recaptured.

The United Nations says that hundreds of thousands of Iraqis have fled Mosul over the past seven months.

June 18: Iraqi forces, backed by coalition air strikes, launch an assault to retake the Old City, where remaining IS fighters are entrenched.

June 21: IS fighters blow up Mosul's iconic leaning minaret and the adjacent mosque where Baghdadi made his only public appearance.

A week later, troops retake the mosque ruins which Abadi hails as a sign of IS's impending defeat. Iraqi forces battle the last few hundred jihadists in Mosul's historic centre.

- Mosul falls -

- July 9: Mr. Abadi declares victory in the "liberated" city during a visit to Mosul, his office says.

This marks an epic milestone for the Iraqi security forces, who had crumbled in the face of an IS onslaught across Iraqi in 2014.

In the final days of the battle, the fight grew tougher as Iraqi forces fought to retake the last two IS-held areas near the Tigris River