Who called from 3478557994

My caller ID showed this number.

Called stating the IRS was filing a lawsuit and it was their last time calling to call this number.  It was a male that called

I received 2 calls from this number today.  They are saying they are from IRs.  I called back to tell them to stop calling me.  First, it just rang and rang and no answer.  The second time I received a busy signal.

They left a message saying they were from the IRS and getting ready to file suit on me. Does anyone know what this is about?

Yes - it's a well known scam!