nfire and explosions marking the opening skirmishes as Iraqi government soldiers began the campaign to retake the City of Mosul from Islamic State. 30,000 troops from the Iraqi security forces, Shiite paramilitaries, Sunni tribal fighters and Kurdish Peshmerga backed by U.S. airstrikes closing in on the city of one and a half million residents.
Intelligence estimates between 4 and 8,000 ISIS militants may be holed up in Mosul, and the city could be laced with tunnels and booby traps. Pentagon officials cautiously optimistic on the initial gains.>> We are on the first day of what we assume will be a difficult campaign that could take some time.
Early indications are that Iraqi forces have met their objectives so far and that they are ahead of schedule for this first day. This is going according to the Iraqi plan, but again, it's early and the enemy gets a vote here.>> Kurdish TV showing the enemy in action.
An ISIS suicide car bomber barrels toward a Kurdish armored personnel carrier and detonates a massive bomb. Kurdish Peshmerga conducting most of Monday's operations seizing several villages east of Mosul. Reuters correspondent Michael Georgy is in Erbil.>> It's the very early stages at the moment, but at this point, I think they're still at the stage where they want to clear several villages and towns so that the Iraqi army and counterterrorism forces can try to sweep into Mosul.
But even that will be done in stages. It's not like they're gonna sweep through the entire city, it's too big and there's about a million and a half civilians. So it's most likely to be slow and strategic movements.>> The Pentagon stressing this is an Iraqi-led operation and the US will provide air support, training and logistics.
But some Americans will be close to combat and the US Special Forces will be operating with Iraqi soldiers.>> The Iraqis will be on the front line, to be sure, Paul. Americans are in harms way as part of this fight.>> The United Nations warning that with so many civilians crowded inside a likely war zone, the battle for Mosul could require the world's biggest and most complex humanitarian effort.