calls cell phone

I didn't answer and they left no message.

these jerks call and tell you the IRS is going to sue you - the IRS never call; will send letter if need be

Calling and never speaking. Get busy signal after a few seconds

Received call from this number.  Caller ID says "Unavailable".  When I answered the phone, I said, 'Hello, Unavailable".  Someone started to say something, and then hung up... oh, dear, another scammer...  They do seem to be becoming more and more frequent, don't they....