With how things have been lately, it might not be an ayakashi, but I'd definitely say it's some kind of spirit. It's too much of a coincidence that the rumours started around the time we started getting possessed objects on the Far Shore, and it is the right season for this sort of thing.

[In Shun's world, that wouldn't mean much, but spirits and the like aren't actually real in his world, so that pretty much voids that excuse here. Not to mention he's already seen a bit of chaos on the Near Shore before now as well.]

It doesn't sound like they've actually caught anyone yet, but that's no reason to get complacent.