Who called from 2028641279

called to say that this was my last warning that the I.R.S. would be sueing me

same here, this morning.
Bogus.  I called back from a private line and they said they were the IRS, I hung up.
Anything due would be sent in the mail, and any returned funds would come in the mail in the form of a check, with details to the refund.

same here- it's a bunch of crap- IRS doesn't call and make threats anyway- they would send a letter

Got this disturbing call sat AM, Seems unofficial will check with our accountant, but sounds like a scam

was called by this number, was a computer voice, said they have been trying to get in touch with me, that the IRS was filing a lawsuit against me.