I have never lost a bird to anything other than raptors, dogs, and racoons. I have had mink problems but they were really distracted from the birds by my rabbits. So basically I am saying, I do not have any first hand experience with mink or weasel kills on poultry. I have collected a decent amount of racoon kill pictures over the years so I will post some if you want to use them as a comparison to your birds.
Attack 1
This one happened over a year ago, it was near the end of winter and I let the birds out, one went off into the barn to lay an egg near dusk and I locked them in without counting. She came back, could not get in, and roosted outside. A coon got her.
Not a lot of eating was done but based on the feather trail from the area she roosted to the area she was stashed the raccoon had dragged her over 100ft after pulling her down and killing her.
This was the only bird killed in this instance, it was also the only one available to kill.
Attack 2
This one happened around mid summer last year. I had a window with a fan in it and a raccoon got in through it during the night. The raccoon had a coop of multiple drakes, cockerels, and roosters to pick from, it tried to kill a rooster but failed and the rooster flew out of the window that the raccoon had broken through. After the coon failed to catch the rooster he killed a drake instead.
The raccoon left the drake in the coop.
Attack 3
This one happened very recently, just on February 6th. My run has a part that is sectioned off and used as a rabbit hutch. So the run has two sections, the hutch is 1/3rd of the run. I thought both sections were completely covered. This was the first raccoon attack on my main coop in well over 2 years. The raccoon found a small hole by a support beam that was tucked away by part of the coop roof 7 feet off the ground. It got into the rabbit section, attacked a rabbit and failed to kill it. Then it was able to go over the door and into the chicken section and had access to the entire flock except for a few cockerels in the other coop. The raccoon decided to kill 3 hens and eat a few eggs.
All three birds had their heads removed and necks eaten. One was more eaten into than the others.
I have one more attack that I documented but don't have access to pictures on this device. I also have a lot of attacks before I joined BYC so at that point I had no reason to take pictures of the killed birds. In every attack I had no more than 3 birds killed in one night, it was usually 1 but sometimes two. I had 3 animals escape being killed by the coon, two later died. 1 miniature rabbit buck, 1 cockerel, and 1 rooster. The raccoons will "cache" their food sometimes. They have gotten into the run twice before, killed a bird, then dragged it out and and hid it. One was in some brush, one was under a boat, and the hen from attack one was under my other chicken coop. This is not the same kind of caching as a mink. As I stated before, I had to deal with mink getting my rabbits. They killed several rabbits every attack and would attempt to cache them all. The thing with the raccoons was not often and was only with one kill at a time.
When the raccoons remove a killed bird from the run it makes the entry point easy to find because it will have feathers around it. Sometimes you will see fur if the coon is in shed. It took me several days to find the entry point on that most recent attack.
Some similarities I have noticed between coon attacks is they attack the head and neck of the bird to kill it and will start eating there too. I have set game cams up last year to observe them scavenge off of kills and they do prefer to eat from the rear on already dead birds. Also, as I said before, I usually only see one victim per night but I have seen two and three kills in one night before. The raccoons do like to feed off their kills for a few days, especially in the winter, because of this they make excellent bait for box traps.
I hope this provided some information about raccoons to you, I am not saying that it was one but just thought I would say my experience with them and see if you thought yours was similar or different.