Transcript for US-backed troops attack ISIS's last stronghold in Syria

Venezuela, thank you. New developments in the battle against ISIS. Heavy fighting is under way right now as american-backed troops attack the terror group's last remaining stronghold in Syria. ISIS now holding on to less than a square mile of territory. Our foreign correspondent James Longman is on the ground in eastern Syria for us. James, good morning to you. Reporter: Good morning, Paula. We're watching smoke rising over baghouz this morning after a night of intense bombardment and can still hear intermitt tent gunfire and during this lull in the fight, we can see ISIS fighters on their bikes and putting up flags. We even heard their battle cries. This fight is not over yet. U.S. Jets and coalition artillery lit up the sky until the small hours. The final push against ISIS is under way. This is as close as again gets to the front line in baghouz. Key can't have too much light to avoid being targeted ourselves. Artillery fire coming from all sides on that tiny town. This is hopefully finally the end of the so-called islamic state. Huge balls of fire and the crash of mortars from all sides. 1500 jihadis remain inside, it is thought. Coalition forces report dozens of ISIS fighters dead. U.s.-backed troops are pushing forward into the town but unclear what they'll find. Booby-trapped building, the hallmark of the ISIS retreat and a network of tunnels stretching for miles. No one knows who or what may be down there. ISIS fighters are freely walking around. Seems they're able to go down in the tunnels and come back up again. I think the tunnels will be a real obstacle for this coalition going forward. Even when this town is cleared, beating their ideology will be far harder to erase. Paula. All right, James Longman reporting from Syria. James, thank you.

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