Left a recording saying that the IRS is filing a lawsuit against me. My CPA said it's a scam. I never called the number back... But it was scary at first however I trust my CPA and he said the IRS will never call you... They would send you cerified mail.
100% fake when I called back and asked why they were calling from a scam number they hung up. Called four times and all four agents (all with what I believe we're Indian accents) hung up as soon as I addressed that they appeared to be a scam.