hamza's home country revoked his citizenship. they believe he is on the afghanistan-pakistan border and could cross into iran. >> somebody like hamza, a younger guy, been in the group since a child is a significant threat. >> reporter: jake tapper, cnn, washington. >> thank you. the push is on there to grab the last bit of territory isis controls. u.s. backed forces say they pushed more than half a mile or 1 kilometers into the enclave. heavy fighting is under way. you can see from this video, a sense of what's happening on the ground. three sdf fighters have been wounded, so far. the operation started friday after civilians were moved out of harm's way. our senior national correspondent, ben, has this. >> reporter: at 6:00 p.m. local time, the forces launched the final operation to clear out