Kurdish Iraqi fighters, backed by US-led coalition warplanes, have launched a major offensive to retake the strategic town of Sinjar in northern Iraq from Islamic State of Iraq and the Levant (ISIL) fighters.
A statement from the Kurdish Regional Security Council on Thursday said about 7,500 Peshmerga fighters were closing in on the mountain town from three fronts in an effort to cut off ISIL supply lines.
Al Jazeera's Imran Khan, reporting from the city of Erbil, said US-led coalition warplanes bombed ISIL positions in the region on Wednesday evening, ahead of what Kurdish officials called "Operation Free Sinjar".
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"What we are hearing is that a number of air strikes have taken place before the offensive began on the ground in the early hours of Thursday. Kurdish Peshmerga troops and Yazidi militias have moved towards the central area under ISIL control," Khan said.
"They say this will be the definitive operation to take the mountain, which is likely to take at least a few weeks. We have seen the Kurdish Peshmerga try this before, but they were pushed back by ISIL for a variety of reasons. But with the coalition getting involved with air strikes, this may well be the final push."
The US-led coalition confirmed it carried out 24 strikes on ISIL targets in and near Sinjar, destroying "ISIL tactical units, fighting positions and command and control nodes".
The KRSC said up to 600 ISIL fighters were believed to be in Sinjar, adding that ISIL had recently sent in reinforcements, including foreign fighters, in anticipation of the offensive.
On the west front, Peshmerga forces secured Gabara village and a stretch of Highway 47 between Sinjar and Syria, cutting off a major supply route for ISIL between Mosul and Raqqa.
"Denying ISIL the use of Highway 47 disrupts their ability to move fighters, supplies and oil destined for the black market," the International Coalition for Operation Inherent Resolve said on Twitter.
Hemin Hawrami, head of the foreign relations office of the Kurdistan Democratic Party (KDP), said Peshmerga fighters entered Sinjar, where they fought "house to house" against ISIL fighters.
The report could not be independently verified.
Sinjar town is strategically important to ISIL because it is on the border with Syria and therefore helps the group maintain a cross-border territory for their so-called Islamic caliphate.
When ISIL took over in 2014 the group killed thousands of Yazidi men and forced families out in an effort to ethnically cleanse the area and bring in people allied to their ideology.
The Kurds see Sinjar town and the surrounding mountain region as part of their territory. This is the second operation the Kurds have mounted there; the first was to open up a corridor to allow the Yazidi community to flee in December 2014.
It was ISIL's takeover of the mountain area and its massacre of Yazidis that pushed the US to begin air strikes in Iraq in August 2014 and the following month in Syria.
Sinjar Mountain was overrun by ISIL in August last year in an onslaught that caused the flight of tens of thousands of Kurdish-speaking Yazidis and first prompted the US to launch air strikes against ISIL.
The group launched a wave of attacks against the minority Yazidi community, members of an ancient religion whom ISIL views as heretics and accuses of worshipping the devil.
The Yazidis fled into the mountains where ISIL fighters surrounded them, trapping and exposing them to the blazing heat.
The crisis prompted the US to launch air drops of aid, and on August 8, 2014, it began its first round of air strikes in what would mark the beginning of a broader coalition effort to battle the group in Iraq and Syria.
Various Kurdish militias on the town's edge have been fighting guerrilla battles for months against ISIL fighters in Sinjar.
The factions include the Turkey-based Kurdish Workers' Party (PKK), the Syria-based People's Protection Units - better known as the YPG - and Yazidi-led forces calling themselves the Sinjar Resistance.
Iraqi Peshmerga have also held positions further outside the town.
The plethora of groups makes the operation to retake the area complex, as they disagree on who will control the area after ISIL is defeated.
|Sinjar was overrun by ISIL in August last year in an onslaught that caused the flight of tens of thousands of Kurdish-speaking Yazidis [Ari Jalal/Reuters]
Source: Al Jazeera and agencies