I would bet money on squirrels - they are destructive little buggers.
Years ago, when I worked in cable, I had a lot of memorable calls. One of them was a call to a home with no service. I rolled up to a brand new house in a nice neighborhood and thought to myself, "This ought to be easy". Usually no service in new residential neighborhoods either meant equipment failure or disconnect in error.
Well, long story short, I head up to her attic where her distribution system was located after confirming that the house was connected properly. It was a walk-in attic and one of the first things I noticed was a lamp and a telephone that were sitting amidst a pile of boxes and such - everything had been chewed to crap. As that was registering, I kept hearing noises above my head and when I finally caught sight of what it was, I realized it was a pair of squirrels. I further noticed that there were peanut shells EVERYWHERE.
I ask the homeowner, "Did you know you have squirrels in your attic?" - She responds somewhat sheepishly and said that not only did she know but she also had been feeding them....
All the wiring in her attic, including her electrical had been chewed down to bare copper. Everything she had stored in there was practically destroyed as well.
So yeah, I don't have much fondness for squirrels. I hope you get things sorted soon, Scott, and that the damage is as minimal as possible - make sure you check your wiring in the attic while you are at it...