Slideshow ( 5 images )

ERBIL, Iraq (Reuters) - Iraqi forces made further gains in their offensive to dislodge Islamic State from Tal Afar, seizing five more villages on the eastern and southern outskirts of the city, the military said on Thursday.

In the fifth day of their onslaught, Iraqi forces continued to encircle jihadists holding out in the city in far northwestern Iraq close to the Syrian border, according to statements from the Iraqi joint operations command.

Within the city limits, Iraqi forces captured three more neighborhoods - al-Nour and al-Mo’allameen in the east and al-Wahda in the west, taking over several strategic buildings in the process.

The advances were the latest in the campaign to rout the militants from one of their last remaining strongholds in Iraq, three years after they seized wide swathes of the north and west in a shock offensive. On Tuesday, the army and counter-terrorism units broke into Tal Afar from the east and south.

The main forces taking part in the offensive are the Iraqi army, air force, Federal Police, the elite U.S.-trained Counter-Terrorism Service (CTS) and some units from the Shi’ite Popular Mobilization Forces (PMF) that began encircling the city on Sunday.

About three quarters of Tal Afar remains under militant control including the Ottoman-era citadel at its center, according to an operational map published by the Iraqi military.

Located 80 km (50 miles) west of Mosul, Tal Afar lies along the supply route between that city - which Iraqi forces retook from IS in July after nine months of fighting - and Syria.

Tal Afar has produced some of IS’s most senior commanders and was cut off from the rest of IS-held territory in June.

Up to 2,000 battle-hardened militants remain in Tal Afar, according to U.S. and Iraqi military commanders. Between 10,000 and 40,000 civilians are estimated to remain in the city and its surrounding villages.