Weird thing about making dead things

I made some dead horses by setting their hit points and constitution to zero along with no decay and their sound set to nothing so they didn’t make a noise as they died. But…

The baddies in the area kept hanging around them ( not attacking just standing around ) and wanting to roam back to them, I changed their faction to hostile and it didn’t happen any more so for some reason although dead they were still seen as a threat.

Quite why this happened I’ve got no idea but be warned, factions on dead things that die when an area loads matter !