I was thinking maybe more than one raptor. I watch our bald eagles often as their nest is just up the river from me. Unless they have eggs or young babies in the nest, they hunt together. We've had this same couple for at least 5 years. Their young is old enough to be left while they hunt and they are out together again. They will sit on either side of the river and watch for salmon. Unfortunately we have very few fish this year due to a hatchery mistake. It is amazing how few ducks I see on the river this year too. So, on the same day, I had the attack I described and my neighbor lost two young chickens and a young duck. Granted we have more birds of prey than just the BEs. It's obvious there is a shortage of food this year for them. Neither of us have any indication that a land predator got inside the runs, and the attacks happened during the day. But, we all live in different areas where we have different sorts of predators. I wouldn't worry about a weasel here because we don't have weasels, for example. I would worry about a raccoon or a cougar. Also I'm assuming they are in a fenced run. Free range presents a whole different puzzle to solve.Sounds more like a Fox or Mink.I just couldn't see a Raptor killing so many birds all at once.Set up some trail camera's and bait the trail cam area with one of the dead chickens. I had a fox take three ducks a few years ago one completely missing the other two were in the far back of my property with there heads completely gone