There would be a religious outcry, specifically from the christian community. To keep the story plausible and real in a real world sense there would have to be such a thing. It would also extend over into general fear... kind of like in the xmen universe where mutants are persecuted and fear because mainly they know nothing of mutants and see them as inferior, barbaric, etc. Thats how I'd imagine muggles would see wizards and witches after they got over the awe of magic itself. Wide spread persecution. Of course, there would be thoes who would not fear them and would try to aide them in what ever way they could.