The Latest on developments in Iraq (all times local):

5:05 p.m.

Iraqi military officials say forces have advanced into the center of the Islamic State-held town of Tal Afar.

Iraqi spokesman Brig. Gen. Yahya Rasool tells the Associated Press that Iraqi forces took control of several neighborhoods Friday as they advanced toward the center of town and are currently at the outskirts of the neighborhood of al-Qalaa.

Brig. Gen. Haider Fadhil of Iraq's special forces, says the U.S.-led coalition provided air cover while Iraqi troops pushed into the town's center. Clashes are ongoing with IS militants, he said.

Tal Afar is about 150 kilometers (93 miles) from Syria's border and it's among the last IS-held towns in Iraq.

On Thursday, U.S. Army Col. Ryan Dillon, the spokesman for the coalition in Iraq, said the militants are "completely surrounded" in the town of Tal Afar and "are being killed."


3:30 p.m.

The spiritual leader of Iraq's Shiite majority is calling on doctors from across Iraq to help civilians fleeing clashes in the latest fight against the Islamic State group in Iraq.

Grand Ayatollah Ali al-Sistani says medical workers should travel to areas around the battle for Tal Afar to help "to treat the wounded and treat them as a humanitarian, national and religious duty."

The call during the Friday sermon delivered by Sistani's representative Sheikh Abdulmehdi al-Karbalai, from the holy city of Karbala comes after the operation to retake Tal Afar began last week. Tal Afar sits west of Mosul, where victory was declared against IS in July. Thousands of civilians are estimated to have been killed in the nine-month fight.

Iraqi defense officials say about 10,000 civilians remain inside the city.