Hawks are pretty territorial within their own species. Larger hawks and eagles will eat smaller hawks, but they'd have to catch them first!
I see all sorts of birds of prey around here. Tons of ponds, and rivers to hunt. We have an absurd amount of bald eagles in addition to red tails, Cooper's, and goshawks. I've only ever had issues with the smaller hawks, as they attack where the birds feel safe — under cover. They do not kill in the same fashion as large hawks. They squeeze their prey to death, or drown them. I have interrupted several attacks, and none had the feather explosion associated with larger birds of prey. I have saved two birds, neither of which had a mark on them. Pretty wild.
Who knows what got your bird. Just be aware that hawks can, and will, kill your chickens through fencing.