I came home from work today to find four of my six chickens killed by something. I didn't see them this morning before going to work as I leave early. I'd lost two of my eight to old age. My chickens normally live a safe, long life. I thought I had done everything to protect them from Raccoons and hawks, the main predators in my area....San Francisco Bay Area. I live in Palo Alto on the Peninsula. However, something got in there either during the night or early this morning. My husband and I never heard a thing and the chicken yard is not that far from our home. Four had their heads torn up and part of their gut opened up. How two survived, I don't know. The feathers are about 30 feet apart. I have not had a predator attack in 12 years!!!! I have fending down to the ground. Red flashing lights everywhere. One clue: When I lost Olivia, I buried her five feet deep in the chicken yard. Two days later I found her body dug up and partially eaten. I think this is what happened to another old lady I lost about two months ago. We couldn't figure it out. Here is my question: Do Possum do this kind of thing. Do they dig from underground and will they attack and kill chickens? Would it have been a Possum that dug up Olivia and then came back? If anyone has any insight, I'd appreciate it. I locked up the other two tight in the large coop tonight. I hope this was not a daytime kill? I'm heartbroken and feel like I failed to keep my chickens safe. Awful.....these girls were about 7 to 9 years old and my pets. Thanks.