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MOSUL, Iraq, Nov. 23 (Xinhua) -- The Iraqi security forces and allied paramilitary units, known as Hashd Shaabi, on Wednesday completely encircled the city of Mosul, while the troops continued operations to clear the Islamic State (IS) militants in and out of Mosul after more than a month since a major offensive was launched, the Iraqi military said.

A soldier from the Iraqi Special Forces takes a selfie on a street in the Aden district of Mosul after troops almost entirely retook the area from Islamic State (IS) group jihadists on November 22, 2016. (AFP/Xinhua)

The predominantly Shiite Hashd Shaabi units advanced to west of the IS-held town of Tal Afar, some 70 km west of Mosul, recapturing six villages and seizing the main road between Tal Afar and nearby town of Sinjar, according to a statement issued by the Iraqi Joint Operations Command (JOC).

The latest advance allowed the Hashd Shaabi units to cut off the IS supply routes from the west side of Mosul, and enabling both the paramilitary units and other Iraqi and Kurdish security forces to entirely isolate and surround the city Mosul, preventing IS militants from moving outside Mosul, the statement said.

The paramilitary units started their advance on Tuesday morning when they moved to encircle the town of Tal Afar, preparing for the next stage to free it from the IS militants.

The units' presence in the whole area in west of Mosul would also enable them to secure the border areas between Iraq and neighboring Syria and would cut off the IS supply routes between Mosul and the Syrian city of Raqqa, the capital of IS self-declared caliphate.

On Nov. 16, the paramilitary troops recaptured a strategic airbase near the town of Tal Afar, which also located some 80 km from the border with Syria.

Tal Afar, held by the IS since June 2014, has majority of both Sunni and Shiite Turkoman people, as well as other minorities of Kurds and Arabs.

The advance of the pre-dominantly Shiite paramilitary units in the ethnically mixed region, where Sunni Muslims form a majority, could spark sectarian tension with Sunni Arabs and neighboring Sunni state of Turkey.

The advance to Tal Afar is part of a massive offensive to dislodge the IS extremist militants from the city of Mosul, which represents their last major stronghold in Iraq.

In southeast of Mosul, the army's 9th armored Division continued their advance toward Mosul and recaptured four villages, the statement added.

In eastern Mosul, the commandos of the Counter-Terrorism Service (CTS) fought fierce clashes with the IS militants as they have been trying to push deeper into the eastern side of the city, locally known as left bank of the Tigris River.

The CTS commandos cleared many buildings of the residential compound in Khadraa district in eastern Mosul after sporadic clashes with IS militants, according to the JOC statement.

However, the CTS forces have met stubborn resistance from the extremist militants, who are fighting in small groups and move quickly. The extremist groups frequently infiltrated behind the advanced CTS forces using tunnels or sneaking through dozens of houses and buildings.

After more than a month of military operations against IS militants in Mosul, almost 68,550 civilians have fled their homes and the number went up every day, according to latest report by the Unites Nations Office for Coordination of Humanitarian Affairs (OCHA).

Prime Minister Haider al-Abadi on Oct. 17 announced a major offensive to retake Mosul, the country's second largest city.

Since then, the Iraqi security forces have inched to the eastern fringes of Mosul and made progress on other routes around the city.

Early in the month, hundreds of the CTS commandos and Iraqi army made a significant progress at the eastern side of Mosul and managed to recapture some 10 districts out of about 60 districts on both sides of the city.

Mosul, some 400 km north of Iraqi capital of Baghdad, has been under the IS control since June 2014, when Iraqi government forces abandoned their weapons and fled, enabling IS militants to take control of parts of Iraq's northern and western regions.