Transcript for US-backed forces find foxholes and weapons near ISIS' last stronghold

We'll stay on top of this. Overseas to Syria where hundreds of ISIS militants and thousands of their wives and children are fleeing the last ISIS strong hold and crowding into refugee camps. One American father travelled to the region looking for his children who he said was abducted by his wife and taken to Syria. Here's ABC's James Longman. Reporter: Victory was meant to be swift, yet U.S., backed forces today finding tunnels, weapons, and even a car bomb. Left behind near ISIS's last stronghold in baghouz. ISIS fighters, some of them injured, have been streaming out of that Syrian town and the wives and children of the so-called caliphate who believed in its fantasy now face the grim reality of its demise. Living in makeshift camps like this one, now at breaking point, another 12,000 arriving in just the last two days. We met one American father who travelled to the region desperate to find two faces among the crowd. Bashirul shikder says his wife abducted their children Yusuf and Zahra from their south Florida home four years ago to join ISIS. I asked her, how you did this to me? How did you come to this kind of decisions to take my lovely Yusuf and my zahara away from me? When I asked her to come back she said that, "I cannot come because our passports, my passport, my babies' passport are taken already." Reporter: His wife now believed to be dead. But U.S. Commanders are warning the seeds of future extremism may be sprouting in those camps. And that father hoping he just finds his children and takes them out of this mess. Tom? James Longman. James, thank you. Next a milestone in space travel after speaks X's dragon

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