Islamic State fighters are keeping 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 frontlines 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 combat ahead is likely to get more deadly as 1.5 million residents remain in the city and worst-case UN forecasts see up to a million people being 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 Major General 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 17.
UN aid agencies said the fighting has so far forced about 10,600 people to flee.
Lise Grande, the UN humanitarian coordinator for Iraq, told Reuters on Tuesday that a mass exodus could happen, maybe within the next few days.
In the worst case scenario, 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, sometimes described as Iraq's second largest, is many times bigger than any other Islamic State has ever 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 Defense Secretary Ash Carter said on Tuesday the attack on Raqqa, Islamic State's main stronghold in Syria, would start while the battle of Mosul is still unfolding.
Turkish Foreign Minister Mevlut Cavusoglu said on Wednesday Turkey would take measures should the Iranian-backed militias attack Tal Afar.
Turkey and Iraq's Shi'ite-dominated central government are at loggerheads over the presence - unauthorised by Baghdad - of Turkish troops at a camp in northern Iraq.
Ankara fears that Shi'ite 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.