UKRAINE'S COUNTEROFFENSIVE INTENSIFIES.

RACHEL SCOTT (ABC NEWS) (Off-camera) Zohreen, thank you. Now to the war in Ukraine. The long-awaited counteroffensive is officially underway, it's likely to be a long and bitter battle, with both sides already claiming early victories. And the international criminal court is investigating a dam explosion that triggered a massive environmental disaster. We want to warn you, some viewers may find some of the images and sounds disturbing. ABC's Tom Soufi Burridge on the ground in Ukraine. [ABSTRACT FROM PUBLISHER]