Cat gets Angry when I clean his box.

This evening when I went to clean out my cat's box, he came in the utility room where the box is kept, started growling and hissing and put a pretty good gash in my leg. I'm at a loss to explain what it was all about. Its never happened before. I suppose he just didn't like me messing with his litter box. Anyone ever experience anything like this?

Thanks,
JT

 

Hi. How has he been since? Is this still an issue?

 

Wow I've never heard of anything like that usually cats want a clean box being such tidy animals.. Is this still an issue? did you smell different that day or maybe he mistaken you somehow??