This is such a sad story. A few years back I took Groucho in for his vet appointment. The receptionist told me earlier that day a woman came in with her cat, the cat wasn't on a leash or in a pet carrier. Well, the cat got away and went crazy in the waiting room. Several people waiting with their pets were attacked by this cat, one seriously enough to be sent to the emergency room. Abigail said there were problems with this same cat in the past like going after the vet while being examined. Don't know what was said, but the vet did talk to the owner about the cat's behavior. I've read that there are some cats who simply cannot be socialized and blend in with humans. Prayers for the owner's recovery and that the vet can find out the reason for the cat's reaction.