special forces in mosul, but fighting still rages with just a few hundred isis fighters left. cnn senior international correspondent nick paton walsh takes us to the front lines. >> reporter: winning here comes only with dust and ruin. this was a day iraqi special forces were meant to take back the symbolic al nuri mosque of mosul's old city but ended up their leaders declared victory while they were bitterly fighting. literally to the side of the mosque is where isis have been. the aim was to encircle the sacred area isis themselves destroyed. [ gunfire ] yet they've lost so many to isis. they moved carefully against an enemy even with high-tech help they rarely see.