I would do exactly what Spudd described. A squirrel is not dangerous, I would not worry even if it is a bird or bates, 99% chance that the animal will not let you get that close to it to risk getting bit or anything like that. I recommend a humane trap that simply traps them in a cage, so that you can carry it away and release it in the woods somewhere, bait it with peanut better.
Even after you catch the first animal, reset the trap a few more times, or alternatively use a couple traps, because you could run into a situation where there is a mom with babies, thus, if you only take mom away and think you are done, the rest will not survive and will still be up in your attic.
the Book YMOYL says that whenever something breaks or you have an issue in your life (like this), it is reason to celebrate because you get to learn a new skill. After you are done taking care of the animals, congratulate yourself on expanding your skill set.