There is a small group of people in the office who have formed a clique of sorts. They go out to eat together, constantly talk to or IM each other, have inside jokes, all sorts of fun stuff. When I started working here around 5 months ago, it seemed like they wanted to initiate me into the group. I have no idea why but I have now been getting IMs from a couple of them during meetings. Perhaps my being polite was mistaken as intent to be non-professional friends?
These IMs range anywhere from idle chitchat to making fun of our coworkers for various things (and usually things that the coworker cannot help, like being nearly deaf and speaking loudly, or a coworker that has a stutter). I'm talking impressions, mocking, and downright trash talking our colleagues. I feel like it goes well beyond harmless joking.
I feel absolutely awful about the things they are saying, and I refuse to take any part in it. How can I distance myself from these people while maintaining professionalism?
Please note I have no desire to reprimand them for their behavior, if that is avoidable. I feel this would only stir up more drama, and make them refocus their ire on me. I am only here to do my job, not judge others for their decisions.