I think it is more likely to be squirrels.

You need to figure out HOW they are getting in. Because eventually, you need to block the opening. You can use insulation, that pink fuzzy stuff that itches? THEY don't like it either.

You can get a have a heart trap, use peanut butter for bait, and catch whatever it is. A squirrel, you want to drive it across a riveer so it can't easily return "home." Can you get into your attic from inside the house?

We had this problem once; Dad forgot and took the dog in the car with him when he took the squirrel (still in the trap) for a ride across the river. Amazingly, the dog just sniffed and ingnored the critter! Only interested when they are running!