hysteria and releasing more defense ministry images of russian troops returning to their bases after completing drills near ukraine. our military has camped on its own territory, says the russian foreign minister, held drills, took down their tents, boarded the trains, then loaded their hardware and started leaving, he says, but the hysterics are still going on. this is where the real escalation is, he adds. but there is dangerous escalation on the ground as well. this is what ukrainian officials say was a preschool hit by artillery shells fired by russian-backed rebels. the rebels say ukrainian government forces pounded their residential areas too. and now ukrainian officials say there's more shelling from the rebel side, sending cnn this video of what they say is a hit on a residential building as tensions near the front lines threaten to spiral out of control.