BAGHDAD -- The Latest on the developments in Iraq as government forces and their allies press ahead in the battle for IS-held city of Mosul (all times local):

7:33 p.m.

The UN humanitarian chief says the United Nations believes up to 1.5 million people in Mosul will be at great risk of being targeted, caught in cross-fire, forcibly expelled or used as human shields during the operation to oust Islamic State extremists from the northern Iraqi city.

Stephen O'Brien said the protection of the elderly, disabled and pregnant women who may not be able to move to safety without assistance cause the greatest concern based on previous evidence of IS practices.

He told the UN Security Council on Wednesday that no large-scale displacement of civilians has been reported on the third day of the Iraqi government-led operation.

But O'Brien said the UN anticipates "a displacement wave of some 200,000 people over the coming weeks, with up to one million displaced in the course of the operation in a worst-case scenario." Of that one million, the UN believes 700,000 would require shelter and emergency assistance, he said.


7:19 p.m.

The chief of the Russian military's General Staff says it has been monitoring the operation to retake the Iraqi city of Mosul from the Islamic State group and is concerned that militants might escape to Syria.

Gen. Valery Gerasimov said Wednesday that "despite all the uproar on Western TV channels, the operation hasn't started in earnest yet."

He said the Russian military was using aerial assets to monitor for "possible attempts by the militants to break out of Mosul or leave the city for Syria unimpeded."

He said: "we hope that our partners from the international coalition realize what could be the consequences of large groups of IS fighters roaming the Mideast region. They must be destroyed on the spot, not driven from one country to another."

Russian warplanes in neighbouring Syria have been carrying out airstrikes for more than a year in support of Syrian President Bashar Assad's forces.


6:33 p.m.

The top commander of U.S. land forces in Iraq says U.S. Army Apache attack helicopters are striking Islamic State group targets in support of Iraq's push to retake Mosul.

Adding U.S. attack helicopter crews to the unfolding combat is an extra element of risk for American troops. Maj. Gen. Gary Volesky said Wednesday the Apaches were being used at night to strike targets from a distance. He said the mere presence of the Apaches was a confidence booster for Iraqi soldiers.

Volesky is commanding general of the 101st Airborne Division. He spoke by video link to reporters at the Pentagon from his headquarters in Baghdad.

Volesky said he believes Islamic State fighters in Mosul will put up a stiff defence in the city but eventually lose and morph into an insurgency.


4:21 p.m.

Turkish President Recep Tayyip Erdogan has suggested that forces he did not name were trying to keep Turkey away from the operation to liberate Mosul because his country was spoiling plans to change the sectarian balance in the region.

Erdogan's comments came amid heightened tensions with Iraq over the presence in northern Iraq of Turkish troops training Iraqi fighters to help retake Mosul. Turkish warnings about sectarian clashes in Mosul if Shiite militia are involved in the operation in the mainly Sunni region also drew Iraq's ire.

In an address to a group of local administrators in Ankara Wednesday, Erdogan said a "scenario" was underway in Mosul "to spark sectarian clashes," adding that was Turkey determined to be part of the Mosul operation to safeguard its stability.

"Our position has nothing to do with war-mongering, with the violation of Iraq's sovereignty or any other ulterior motive," Erdogan said. "We want to be present wherever we need to be to protect our freedom and future. That place at the moment is Mosul -- therefore we will be in Mosul."

The Turkish leader reaffirmed that U.S. officials had agreed to the Turkish air force's participation in the U.S.-led coalition. He said efforts were underway toward a wider Turkish participation.

Erdogan also said his country had taken in 300,000 refugees who fled the violence in Iraq and warned Iraq's leaders against losing Turkey's friendship.

"You can never find such a friend. If you hurt this friendship you will lose."


1:40 p.m.

An aid group says thousands of Iraqis are fleeing to Syria in order to escape the fighting around the northern city of Mosul, where a wide-scale offensive is underway to drive out the Islamic State group.

Save the Children said on Wednesday that 5,000 people have arrived at the al-Hol camp in northeastern Syria from the Mosul area in the last 10 days, with 1,000 more waiting to enter at the border.

The group says the camp was ill-equipped to receive the refugees, saying it is "littered with waste and feces, with a looming risk of outbreaks of disease." It says there are just 16 latrines shared by more than 9,000 people, many of whom only have access to dirty, untreated water.

Tarik Kadir, head of Save the Children's response to the Mosul crisis, says that "conditions there are among the worst we've seen, and we expect thousands more people to be on their way soon."

Mosul, which fell to the Islamic State group in 2014, is still home to more than a million civilians.


1:30 p.m.

A Turkish official says between 100,000 and 400,000 people could flee the fighting in Mosul and make their way toward Syria, Iraq's Kurdish-administrated region or the border with Turkey.

Kerem Kinik, head of the Turkish Red Crescent organization, told The Associated Press on Wednesday that the "humanitarian aspect" of the Mosul operation had not been well thought out by the coalition forces.

He warns that with more than 3 million people already displaced in Iraq, officials would struggle to cope with the exodus. Kinik says his organization was working with officials in northern Iraq and the Iraqi Red Crescent to help support humanitarian efforts there. Some 20 Turkish aid trucks had been dispatched to the region.

New camps for up to 20,000 families are under construction by international aid agencies in northern Iraq and could be ready within a week.

The Turkish official said he believes the refugees would mostly be "taken under control" within Iraq, but added that Turkey is prepared for a refugee influx.


1:10 p.m.

A senior Iraqi military commander has called on local fighters with the Islamic State group inside Mosul to lay down their weapons as a wide-scale operation is underway to retake the city.

Lt. Gen. Talib Shaghati, told reporters at a military base on Tuesday that up to 6,000 IS fighters are still inside the city. He did not say how many of them are foreigners.

IS captured Mosul, Iraq's second largest city, when it swept across much of northern and western Iraq in the summer of 2014. The group has suffered a string of defeats over the past year, and Mosul is its last major urban bastion in Iraq.

The push to retake Mosul is the biggest military operation in Iraq since U.S. troops withdrew in 2011.


12:45 p.m.

Iraqi and Kurdish authorities are setting up a refugee camp with some 5,000 tents east of Mosul as they brace for an influx of people fleeing a massive offensive to retake the Islamic State-held city.

Project manager Prezzo Mikael said on Wednesday that the camp is nearly complete, with running water, electricity and food.

The massive operation launched on Monday is expected to take weeks or months. Mosul, which fell to IS in 2014, is still home to more than a million people. The camp is prepared to receive 5,000 families.

Iraqi authorities have called on people to remain in their homes, but are also preparing humanitarian corridors for them to escape the fighting.


11:30 a.m.

Islamic State militants have deployed suicide car bombs and fired mortar rounds to slow down the advance of Iraqi troops outside a key town near the militant-held city of Mosul.

An officer with the Iraqi army's 9th Division told The Associated Press on Wednesday that his troops are around 1 kilometre (half mile) away from Hamdaniyah, a historically Christian town also known as Bakhdida.

He says IS has sent 12 car bombs since Tuesday, all of which were blown up before reaching their targets. He says troops suffered a small number of casualties from the mortar rounds, without providing figures.

The officer spoke on condition of anonymity because he wasn't authorized to talk to reporters.

Iraq launched a massive operation on Monday to retake Mosul, the country's second largest city.

Qassim Abdul-Zahra in Khazer, Iraq