Transcript for Forces Converge Around Mosul for What Could Be an All-Out Battle Against ISIS
killed in a shooting. It remains under investigation tonight. Overseas to Iraq, where an all-out assault to take back mosul is imminent. The country's second largest city is a vital stronghold for the terror group. Alex Marquardt, reporting from the front lines tonight. Reporter: Battered humvees and trucks full of soldiers rolling out, as tonight Iraq braces for an all-out battle with ISIS that could begin within hours. Some 30,000 troops are massing around mosul, backed by U.S. Special forces advisors on the ground and American jets carrying out airstrikes. ISIS has held the city for over two years and is digging in to defend its biggest prize. Burning oil and tires for cover, digging tunnels and setting booby traps for the advancing forces. Today, we visited a base overlooking the frontline. The kurdish forces there manning a post, face-to-face with the enemy. This base is the closest one to the ISIS positions in this area. In fact, we can see an ISIS flag on the next ridge over, just under a mile away. It routinely comes under mortar and sniper fire. These fighters have lost friends here. And they tell us they are impatient for this battle for mosul to get under way. Including farhang, who didn't want his face shown for security reasons. He left a life in Canada to fight ISIS. ISIS is probably one of the worst terrorist organizations we have ever seen, in history I think, probably. And I think it's very important for everybody that can do something to stand up and fight back. Reporter: The Iraqi military has dropped leaflets on mosul telling residents to stay away from ISIS positions. Around 1 million people are expected to flee the fighting in what the U.N. Says may be the biggest humanitarian crisis this year. Tom?
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