User blog comment:MilitaryBrat/Lord Voldemort vs Darth Vader/@comment-181289-20111217025951/@comment-4661256-20111217051824

I quote from Harry Potter and the Half Blood Prince: Chapter 2, Spinner's End, Pages 19-20:

"The fox froze, wary eyes fixed upon this strange new phenomenon. The figure seemed to take its bearings for a few moments, then set off with light, quick strides, its long cloak rustling over the grass...." (Bellatrix Lestrange, in this scene) ... "There was a flash of green light, a yelp, and the fox fell back o the ground, dead."

As you can see, no words were uttered at all during this process.