Matt,
It's likely EMS traffic to a distant hospital.
Back in the 80s, I was a medic in Georgia. We had to "dial-up" the specific hospital to talk to the ER. Using 155.340, I could sit (at night especially) and hear remote stations and mobile units. Some times you could hear the tones, especially if someone dialed 133333 (the all-call/emergency tone, which opened all radios).
If your scanner is newer than 1996, then you wouldn't likely receive a cellular phone transmission. Of course, I won't say never.......bleed over from adjacent towers, etc. is possible....not probable, though.
Now, if you could catch the callsign, you could look it up (wireless.fcc.gov) to see who it belongs to....