Well, being in Alaska our predators are not as common as those of you in the lower 48's. (which is what we refer to all of you outside of AK and HI).
But, I recently suffered a loss of my small "flock" (3 Golden Comets). I had begun free ranging my girls on my acre in the "suburbs" and had always supervised the free range sessions (more like babysitting). One day, for only 10 unsupervised minutes, they were all killed (murdered). I noticed from my window that 1 girl was laying down in the yard and I called for my kids to help me investigate. By the time we all got to that area she was gone but we discovered her other 2 roomates were killed. We found the 3rd in a neighbors yard and the evidence all pointed to the same type of killer. They were not eaten but slashed and like degutted.
We think that the predator will return to their source of food and are guarding the relacements. So, ruling out wildlife, our predator is someone's unsupervised pet and you can bet that they will return. Think of installing a low wire electrified type of fencing, that is our next step of "insurance" for our girls. I cross my fingers every morning I check on my new girls, and sadly I'm afraid to let them free range. Good luck and keep a tight observation of pets and nearby threats.!