Weasels do often take their food.
I had a weasel come and drag it's food under the coop.
But I doubt a weasel would drag a dead chicken through the woods.
I would say coon because they are tricky, sly little beasties.
But, from what I've hear about raccoons I wouldn't think they carry the bodies away.
It's hard to say when you don't have a lot to go on, but I would assume raccoons before a fox.
So sorry for your loss by the way.
He was a...