LIVE BLOG: The battle for Mosul

The Turkish Red Crescent is sending trucks of aid to northern Iraq with enough food and humanitarian supplies for 10,000 people displaced by fighting in Mosul, the president of the agency said on Friday.

"In the first stage, we are sending this aid to the nearly 30 villages around Mosul that have been liberated. There are 3,000 to 4,000 people on the move from those villages, the trucks aim to reach them," Kerem Kinik told Reuters.

He said between 150,000-400,000 people could ultimately be displaced from Mosul and that additional camps were being built by Turkish aid agencies in northern Iraq in preparation. The Red Crescent said in a statement it was sending 20 trucks, with supplies including dried food, clothing and several hundred tents and beds.

Iraqi and Kurdish forces pursued operations on Friday to seize territory around Mosul in preparation for a long-anticipated offensive on the militants' last major stronghold in Iraq.

Fighters from the Kurdistan Workers Party (PKK) are heading to the Iraqi city of Kirkuk to help fight against the Islamic State group, according to the Kurdish Dicle News Agency (DIHA).

Clashes erupted in Kirkuk on Friday after an apparent IS sleeper cell activated itself in the city. At least six policemen and 12 IS fighters had been killed in fighting, mostly in southern neighbourhoods.

Local government officials have previously denied the presence of the PKK, who are politically at odds with the Iraqi Kurdish government, in the city.

A member of the US military was killed on Thursday in a bomb blast north of Mosul, a senior US defense official said, as Iraqi forces in the region continued their push on the city.

The official told AFP that the service member had died in what were likely "Mosul-related" operations, but did not provide additional details.

More than 100 US troops are advising Iraqi security forces and Kurdish peshmerga as they advance toward Mosul, the Islamic State group's last stronghold in Iraq, on multiple fronts.

Officials did not immediately identify the service member and the US-led coalition fighting IS said further information would be released "as appropriate" -- additional details often depend on when family members are notified of the death.

An unnamed US official cited by CNN said the service member was medevaced off the battlefield but later died from the wounds. No other US troops were wounded, CNN said.

The death is the fourth time a US military member has been killed in combat in Iraq since operations against IS began there in 2014.

In May, Navy SEAL Special Warfare Operator 1st Class Charles Keating was fatally shot during a pitched battle with IS near the village of Tal Asquf, north of Mosul.

In April, Staff Sergeant Louis Cardin was killed by an IS rocket attack that also wounded eight Marines at an artillery position in the Makhmur area of northern Iraq.

And in October last year, Master Sergeant Joshua Wheeler, an American special operations soldier, was killed during a joint raid with Kurdish forces against IS in Hawijah, a northern Iraqi town.

A senior US general has suggested that the battle for Mosul "could last longer than a year".

Speaking on behalf of the US led coalition against ISIS, General Joseph Votel added: "It certainly will be a difficult operation and IS has certainly had a long time to prepare for this operation."

The US does not support the Shia-majority militias taking part in the offensive against IS in Mosul, a military official said on Wednesday. 

"As far as the Shi'ite PMF [goes], the coalition only supports those elements that are under the direct command and control of the Iraqi security forces, and the Shi'ite PMF are not," Major General Gary Volesky, the commander of US-led coalition ground forces in the fight against Islamic State militants, said.

"So we don't support them."

The participation of the Popular Mobilisation Forces, a group of Shia-majority militias, in the offensive on mainly Sunni Mosul has raised fears of reprisals against civilians when advancing forces reach the city.

Members of the PMF taking part in the offensive told Middle East Eye on Wednesday that they "do not seek revenge, but we want assurances that our people are going to exist tomorrow and not be attacked again by extremists."

The US is prepared to send additional Apache helicopters to aid the forces currently advancing on IS-held Mosul, a Pentagon spokesperson said on Monday.

There are already US troops giving "logistical support" to the forces, the spokesperson said.

However, the Pentagon believes that Iraqi forces - which currently include Kurdish troops and Iran-backed militias - are "capable of retaking Mosul".

The spokesperson did not specify how many helicopters will be made available for the battle.

The Islamic State (IS) group are setting fire to oil wells in Mosul, reportedly to obscure the vision of coailtion airplanes as the militant group makes its retreat.

The images have evoked memories of the first Gulf War for many Iraqis, some of whom see IS's use of similar tactics to those of Saddam Hussein in 1991 as further evidence of the Baathist presence within the militant group.

Translation: "From the outskirts of Mosul right now: after IS fighters set fire to oil wells"

Translation: "IS are burning oil wells in southeast Mosul, because it thinks it will prevent the airplanes from spotting them. They are repreating the Baathist mindset - we are in 2016 not 1991"

Translation: "IS are bruning oil wells in Mosul before they retreat. Evidence that they are Baathists. The same crime of burning oil wells in Kuwait before they were expelled. A rotten mentality."

Turkey's air force has been involved in coalition air strikes on the Iraqi city of Mosul, part of the US-backed operation to flush out Islamic State, Prime Minister Binali Yildirim said on Tuesday.

Turkey has been locked in a row with Baghdad about the presence of its troops at the Bashiqa camp in northern Iraq and over who should take part in the US-backed assault on Mosul. Turkey has trained up to 3,000 forces taking part but is concerned the operation could stoke sectarian tensions.

The operation to liberate Mosul from IS forces may lead to a flood of refugees displaced from their homes due to the fighting, the UN warned today according to AFP.

"It's a trickle right now," Lise Grande, the UN's humanitarian coordinator in Iraq, told journalists, referring to displacement caused by the operation.

But "our expectation, based on what the military has briefed us, is that if we start to see significant population movements, it's likely to be within five to six days," Grande said.

"So as they're moving toward the city, there is not an expectation that we're going to have mass outflows. But the military has said that... we could see that within five to six days," she said.

According to Grande, 200,000 people being displaced "is a working scenario" for what might happen "in the first couple of weeks" - a number that may rise significantly as the operation goes on.

The UN has previously warned that the operation may spark a humanitarian crisis, displacing up to a million people.

Iraqi Kurdish peshmerga forces have taken several villages east of Mosul in coordination with Iraqi federal forces and air support from the US-led coalition, according to AFP.

Peshmerga commanders said the push was part of the ongoing operation to liberate Mosul from IS, and that villages taken today used to be inhabited by members of the Christian and Kakai minorities.

The operation included “up to 4,000 peshmerga in three fronts to clear nearby IS-occupied villages," the general command of the peshmerga said in a statement.

The heavy influence of Shia militias in the Iraqi operation to retake Mosul, and their history of sectarianism in other liberated regions of Iraq, have some questioning the future of Mosul's residents.

The risk of further displacement of Iraq's Sunni community has received particular emphasis.

Translation: "IS attack a Sunni area. Iraqi forces withdraw. IS control the area and kill people. IS withdraw. Iraqi forces return to kill Sunnis under the pretext of IS being within their midst #The_lie_of_IS"

Translation: "The world will witness on live air the annihilation of Mosul and the continuation of displacing Sunnis from Iraq in the name of the war against IS"

Translation: "The Islamic State group. It is a political trick to kill Sunnis and displace them from their regions"

Pro-Islamic State (IS) group accounts on Twitter are relaying reports from the militant group's media wing, al-Amaq news agency, on their succesful attacks against Iraqi and coalition forces.

Translation: "One bulldozer has been destroyed and another damaged, both belonging to Iraqi forces, in the southern town of al-Houd in south Mosul"

Translation: "One Hummer vehicle has been destroyed and another damaged, and two bulldozers have been destroyed, all belonging to the Peshmerga, in the village of Baskhera"

Translation: "Two Hummer vehicles belonging to the Peshmerga forces and the Shia al-Hashd (al-Shaabi) have been destroyed in the town of Kabrily, east of Mosul"

Our interactive editor has produced a slide map to show the scale of IS defeats since its height in June 2015. If Mosul falls, the group will have no major city under its control in Iraq.