Iraqi general calls on IS militants in Mosul to surrender

Over the past day, IS sent 12 car bombs, all of which were blown up before reaching their targets, he said, adding that Iraqi troops suffered a small number of casualties from the mortar rounds.

Some 25,000 troops, including Sunni tribal fighters, Kurdish forces known as the peshmerga and state-sanctioned Shiite militias known as the Popular Mobilization Units are approaching the city from different directions.

Amnesty International said in a report released Tuesday that Iraqi government and paramilitary forces detained, tortured or killed hundreds of Sunni Arab civilians fleeing IS-held areas during the operation to retake the Sunni city of Fallujah, west of Baghdad, earlier this year.

The Iraqi government has denied any systematic violations by security forces or the militias, and says individuals have been held accountable for occasional abuses.