invasion the costliest mistake that the kremlin has ever made. and the hit to russia s economy must be proportionate to the unprecedented atrocities that we are seeing. the dead bodies are piling up in bucha as officials search this once-affluent outer suburb of kyiv. and increasingly, the dead show signs of torture. satellite images show mass graving were being dug in bucha as far back as march 10th, two weeks after the russian invasion began. we have more details now from cnn s fred pleitgen. but first, another warning, the images you will see are disturbing and graphic but they reveal the brutality and sheer cruelty of what happened in bucha under russian occupation. reporter: ukrainian authorities in bucha lead us into a basement they call a russian execution chamber. it s a gruesome scene. five bodies. their hands tied behind their backs, shot. the bullet casings collected by