I assume you are on the North American continent from your screen name and your mention of raccoons. It's possible you have bantams, again because of your screen name.
Most predators will leave the bodies behind but some might carry them away. Flying predators tend to eat where they kill unless they have babies in a nest to feed which is unlikely this time of the year. It takes a relatively large flying predator to carry off a body, an eagle or large hawk, but if they are bantams it would be easier. I doubt it is a flying predator.
One suspect is a canine. Possibly a dog but more likely a fox or coyote. When I was a kid Dad had a fox visit every morning at daybreak and carry off one chicken. I happened to see it as it grabbed a chicken and carried it off. Dad had to wait until Saturday and he wasn't at work to shoot it. Something like that could be going on.
Another possibility is a big cat like a bobcat. They tend to take one at a time and carry it off a short way to eat it, burying the remains to come back and finish it later.
Fox, coyote, and bobcat can and often do live within city limits, let alone in the countryside. People think they are not around because they don't see them but they often are. I could be wrong but it sounds like something like this could be going on.
