Iraqi forces pushed toward Mosul "ahead of schedule" on the first day of their offensive aiming to drive Islamic State forces out of the country's second largest city. Pentagon spokesman Peter Cook said the battle "could take some time" but it was not yet clear whether ISIS would retreat or "stand and fight." The American general in charge of the coalition's anti-ISIS war in Iraq and Syria, Lt. Gen. Stephen Townsend, acknowledged that U.S. "forward air controllers" were participating in the offensive to help with targeting for the U.S.-led air coalition's airstrikes in support of the Iraqi forces.

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