I have heard the same TG on MARCS down here in Hamilton County. I have heard various traffic on it. To me it sounds like "local" PD traffic but I have never heard any ID's or anything. I have been hearing it for about a week.
It could be MedCorp EMS, there was a thread that they were using MARCS now for some activity in SW Ohio. I heard that talkgroup as well up here in Toledo (MedCorp home office). I have not heard much further to confirm though.