Kurdish Fighters Trying to Hold Off ISIS.
COSTELLO: Just a couple of hours ago, we learned there is a major new player in Syria. That major new player would be Iran. Iran says it will send its foreign minister to peace talks in Vienna. Russia says it was the United States that invited Iran, which has now emerged as the major player in this conflict, on the battlefield. The U.S. says it has dropped ammunition to a new rebel alliance that includes Kurdish fighters taking on ISIS and who desperately need more weapons, armor and ammo. CNN senior international Clarissa Ward has been on the front lines. She joins us now from Erbil in Iraq. Hi, Clarissa.</s>CLARISSA WARD, CNN SENIOR INTERNATIONAL CORRESPONDENT: Hi. Good morning, Carol. Well, we spent times in recent areas that have been liberated from ISIS. But you don't find people celebrating on the ground, and that's because the devastation the fighting has left behind is enormous and the future is still uncertain.</s>WARD (voice-over): Weeks ago, these dusty planes were held by ISIS. This is what's left of its presence now. The charred remains of a training camp hidden in a pine forest. It's where ISIS trained an elite unit of suicide bombers that attacked Kurdish positions with devastating effect. Kurdish fighters known as the YPG took this entire area from is in August, but holding it along a front line more than 400 miles long is a huge challenge. In the shadow of Mt. Abdulazeez, Commander Zinar told us he had lost 30 of his fighters in a recent battle when ISIS came down from the mountain.</s>CHIEF ZINAR, YPG COMMANDER (through translator): The enemy attacked us with a large number of fighters, using heavy weapons. They took control of three villages and after that, the clashes lasted for hours until we were in control again.</s>WARD: Zinar is a battalion commander, but this is the size of his battalion, a handful of poorly equipped men. The nearest friendly forces are miles away. The cost of pushing ISIS out has been enormous. Streets here are draped of the flags of fighters killed in battle, along desolate roads, through abandoned villages, we saw scene upon scene of devastation. The wreckage of months of fierce fighting and relentless coalition airstrikes. (on camera): Dozens of villages like this one that were liberated from ISIS months ago are now still completely deserted.