Iraqi forces have begun an operation to banish so-called Islamic State from one of their last remaining strongholds in the country.
Iraq's prime minister warned IS fighters had "no option" but to "surrender or die" as he announced the move on Tal Afar, a key town west of Mosul, in a televised address.
"The city of Tal Afar will be liberated and will join all the liberated cities," Prime Minister Haider al-Abad said early Sunday.
It is estimated between between 10,000 and 50,000 people remain living in and around Tal Afar.
In the past, so-called Islamic State has prevented civilians from fleeing and used them as human shields in an attempt to slow Iraqi advances.
The UN has expressed concern over the safety of those living near Tal Afar, threatening to compound a humanitarian crisis sparked by the operation to free Mosul from so-called Islamic State.
Some 49,000 people have fled the district since April, according to the United Nations, with almost one million people still displaced following the nine-month campaign to retake Mosul.
The UN Humanitarian Coordinator for Iraq, Lise Grande, described the situation inside Tal Afar as "very tough", with food and water running out and many lacking basic necessities.
"Families are trekking for 10 to 20 hours in extreme heat to reach mustering points," she said. "They are arriving exhausted and dehydrated."
By early afternoon on Sunday, Lieutenant General Abdul-Amir Rasheed Yar Allah, who commands the operation, said the forces had recaptured a series of villages east, south-west and north-west of the town.
The US-led coalition providing air and other support to the troops praised what it said was a "capable, formidable, and increasingly professional force".
They are "well prepared to deliver another defeat" to so-called Islamic State in Tal Afar, like in Mosul, the coalition said in a statement.
The operation on the Sunni extremist IS group could heighten sectarian and regional tensions as it will involve both Shiite and Sunni militiamen. Shiite militiamen sat out the operation to retake the mostly Sunni city of Mosul.
Tal Afar, which is about 90 miles east of the Syrian border, sits along a major road that was once a key IS supply route.
The city and surrounding area forms one of the last pockets of IS-held territory after the group lost Mosul, the country's second-largest city, in July.
"My message to (IS): you (have) no option, you either surrender or die," Mr al-Abad declared in the TV address.
"We prevailed in all battles against (IS), while (IS) faced death and defeat in all their battles."
Tal Afar was home to both Sunni and Shiite Turkmen before it fell to IS last year, with the town's ethnic Turkmen community maintaining close ties to neighboring Turkey.
Turkish officials have expressed concern that once territory is liberated from IS, Iraqi Kurdish or Shiite forces may push out Sunni Arabs or ethnic Turkmen.
Along with Tal Afar, so-called Islamic State are still in control of the northern town of Hawija as well as Qaim, Rawa and Ana, in western Iraq near the Syrian border.