They called me with a notice that this was IRS and that they were going to file lawsuit. Called them back via Anonymous Google Voice number (so they would not know who returned the call) and in a heavy accent they answered the call and pretended to be IRS. When I asked them a question they hung up. Tried 3 times, twice the same person. Do NOT return the call or provide information. Just block the number.

Same.  Call came from (619) 366-4270. Voicemail message asked me to call back this number.  I didn't bother.  Said they're the IRS and filing a law suit.  I just reported it as a scam to Privacy Star and blocked the number.

same as above. We are a business and have accountants, the caller claimed they were IRS and going file a suit. the IRS would not do this so this is a pretty stupid scam artist.