We've had problems like that with squirrels, too! They were in our high attic (over the second floor, nothing up there but a heating system) and I threw strong moth balls up there. Didn't realize I was blocking their escape route, so they came down into the lower attic (walk-in, floored, stuff stored there) and the back screened porch. Others chewed their way into the garage from outside.

I hate squirrels!

We have coyotes around here, and deer, but I don't think I've seen any foxes. Be careful, Olivia!