Lost three chickens outta five within 36 hours inside the coop!( I use coop & enclosure interchangeably.) Anyway we used the"dog run" that came with our house,its at the back of yard and turned it into a chicken coop. Basically a 9"x24"- 4 sided fence with concrete floor, built the hen house, then put 4 or 5 sections of chicken wire on the fence to enclosure the coop. I used zip ties to hold the chicken wire tight so no Hawks could squeeze through the top of the enclosure. When we built the hen house we added locks to the nest box door & the door I use to access house easily. The hen door does not have a lock but opens up & down on a pulley.I had it opened so the hens can come & go as pleased. Wished they had ran inside it to escape! I live in central/northern Illinois. country but I live in town. At 4pm only 3 hens greet me. odd, I noticed a hen is missing, the other hen murdered in the back of the coop. Hens neck looked naked, meat missing from side, obvious predator attack! But how did the predator take a chicken? It didn't drag it away, it had to of taken the hen from the top of the fence. I did notice one spot where there's a space it could have fit through. Somehow it squeezed the 5lb prey through a very small opening on top. So I removed the carcass & while cleaning up I saw a hawk circling overhead.Then I got metal wire to wrap it around the chicken wire/ top of the fence, leaving no space for a hawk to fly in. No way was a hawk getting inside now! The remaining 3 hens seemed fine, gave em some treats & wondered the yard. I put them back into the enclosure around 6pm. I look up some info online & start to worry. We grab flashlights & checked on coop. One hen was walking the front fence, squawking loudly, frightened. I knew something had been inside. The barred rock was lying dead under the hen house . Now another hen victim! The other Hen was in the house. What is coming in, likely evening/ night that can climb a 6ft fence, and sneaks a 5lb bird over that fence? left bigger hens behind. After finding the 3rd victim tonight around 10pm, I put the remaining two hens in the house and shut their door & checked locks. I still have to dispose of the hen, in the morning I will look for footprints since its been rainy & try to check the carcass for more clues as to whats getting in. Im just baffled & feel violated. We were getting almost a dozen of eggs every 2 days. dman Any help is appreciated! update from last night. Its a raccoon, I think. no weasels in town. My neighbor showed me two legs with the bone attached, in his yard. As I was cleaning up his yard I found the rest of the carcass 10-20feet up the tree. The other hens head was ripped off and eaten, the skull left behind. . I do see where the coon pulled back the wire from the fence.