I am terribly sorry this has happened to your flock and your family. The shock and distress when you go outside to find something like this is unthinkable. I hope you are able to find out what happened and save whats left. Predators are difficult to deal with - I was recently looking into a solar powered post topper that has a blinking red light - supposed to mimic another predators red eye and deter them from coming in? A local gentleman here says it really has reduced his losses to fox, coyotes, dogs, raccoons, etc that come off of the fields onto his property. I'm sure others know more about the pros and cons of it. I also dont know if they are effective against smaller predators like weasels, which this sounds suspiciously like it may be? I lost all but 3 of my chickens/hens out of all of my geese, turkeys and chickens this year - to my own dogs. Take care of yourself - Keep everyone updated and let us know that you are okay, and how the handful of chickens that are left are doing?