Islamic State fighters have kept up their fierce defence of the southern approaches to Mosul, which has held up Iraqi troops on the southern front and forced an elite army unit east of the city to put its more rapid advance on hold.
Ten days into what is expected to be the biggest ground offensive in Iraq since the US-led invasion of 2003, army and federal police units aim to dislodge the militants from villages in the region of Shora, 30km south of Mosul.
The front lines in other areas have moved much closer to the edges of the city, the last major stronghold under control of the militants in Iraq, who have held it since 2014.
The elite army unit which moved in from the east has paused its advance as it approaches built-up areas, waiting for the other attacking forces to close the gap.
"As Iraqi forces move closer to Mosul, we see that Daesh resistance is getting stronger," said Maj Chris Parker, a coalition spokesman at the Qayyara airbase south of Mosul that serves as a hub for the campaign. Daesh is an Arabic acronym for Islamic State, also known as Isis or Isil.
The combat ahead is likely to get more deadly as 1.5 million residents remain in the city. According to worst-case UN forecasts, up to a million people could be uprooted. A Reuters correspondent on the southern front met villagers and police who said their relatives had been taken as human shields to cover the fighters’ retreat from the area.
The militants have been using suicide car-bombs extensively to fight off the advancing troops, according to Maj Gen Najm al Jabouri, the commander of the Mosul operations. He said his soldiers had destroyed at least 95 car bombs since the battle started on October 17th.
Outside the village of Saf al-Tuth, Maj Gen Jabouri directed heavy machinegun fire at a sparse concrete building on a ridge where his men believed a sniper was hunkered down. Volleys of rockets flew over the ridge and pounded the village itself with loud booms.
Mass exodus
UN aid agencies said the fighting had so far forced about 10,600 people to flee.
Lise Grande
, the UN humanitarian co-ordinator for Iraq, said that a mass exodus could happen, maybe within the next few days.
In the worst-case scenario, Ms Grande said it was also possible that Islamic State fighters could resort to “rudimentary chemical weapons” to hold back the impending assault.
The fall of Mosul would mark Islamic State's effective defeat in Iraq. The city, Iraq's second largest, is many times bigger than any other Islamic State has captured, and it was from its grand mosque that the group's leader Abu Bakr al-Baghdadi declared a "caliphate" that also spans parts of Syria.
US defence secretary Ash Carter said the attack on Raqqa, Islamic State’s main stronghold in Syria, would start while the battle of Mosul was still unfolding.
A senior US official said about 50,000 Iraqi ground troops were taking part in the offensive, including a core force of 30,000 from the government’s armed forces, 10,000 Kurdish fighters and the remaining 10,000 from police and local volunteers.
Iraqi army units are deployed to the south and east, while Kurdish fighters are attacking from the east and the north of the city, where 5,000-6,000 jihadis are dug in, according to Iraqi military estimates.
Coalition air power
There are also roughly 5,000 US troops in Iraq. More than 100 of them are embedded with Iraqi and Kurdish peshmerga forces advising commanders and helping coalition air power in hitting targets. They are not deployed on front lines.
The attacking forces are set to increase soon if Iranian-trained Shia militias join Iraqi forces, although their presence is contentious because of concern that they could alienate mainly Sunni Muslim residents of the area.
The militias, known collectively as Hashid Shaabi, or Popular Mobilisation Forces, said last week they would help the army take back Tal Afar, a mainly ethnic Turkmen city west of Mosul on the road linking Iraq to Syria.
Iraqi defence ministry spokesman Brig-Gen Yahya Rasool told Al-Sumariya television channel that the PMF would open a new front in Mosul in the coming days, but gave no details.
Hadi al-Amiri, head of Badr, the most powerful group within the PMF, was expected to give a news conference later.
Turkey's foreign minister Mevlut Cavusoglu said Turkey would take measures should the Iranian-backed militias attack Tal Afar.
Turkey and Iraq's Shia-dominated central government are at loggerheads over the presence – unauthorised by Baghdad – of Turkish troops at a camp in northern Iraq. Ankara fears that Shia militias, which have been accused of abuses against Sunni civilians elsewhere, will be used in the Mosul offensive.
The Iraqi army said it had regained full control of the mainly Sunni western town of Rutba on Wednesday, three days after Islamic State attacked it, in an apparent effort to divert Iraqi government troops from the assault on Mosul.
The militants at one point controlled half of the town on a key route to Syria and Jordan in Anbar province, a hotbed for the largely Sunni insurgency against Shia-led government.
Reuters