A U.S. service member in Iraq was killed Saturday by an explosive device outside Mosul, according to a statement released by the Pentagon.

Islamic State militants had banned toys with unveiled faces as well as anthropomorphic animals, which they deemed a form of idolatry.

Iraqi police accused Islamic State of using chemical weapons against their forces, but said that had not stopped them making new ground towards the militants' last stronghold in Mosul.

The American confirmation came after Iraqi forces paused their drive to recapture west Mosul because of the high rate of civilian casualties.

U.S.-backed Iraqi forces launched a major air-and-ground offensive Sunday to retake western Mosul from Islamic State militants and drive the extremist group from its last major urban bastion in Iraq.

Iraqi planes dropped millions of leaflets on the western side of Mosul warning residents that the battle to dislodge Islamic State is imminent as troops began moving in their direction

“I finally found out what racism was when I joined the military,” Defence Minister Harjit Sajjan told Global News in a one-on-one interview.

Residents are fleeing Mosul as Iraqi forces push into the city and Islamic State extremists fight back, using civilians as human shields.

Canada promised the hospital in July in advance of the Iraqi military offensive to retake Iraq's second-largest city, Mosul.

ISIS militants in the Mosul area are recruiting child soldiers and abducting civilians for possible use as human shields, as Iraqi and coalition forces drive into the region.