Received two urgent calls from this phone, ID is "NOT AVAILABLE", the same message as described by DH above. IRS will never hide their ID, I think, so, in my opinion, this is a scam. I found this info on IRS website about phone scams http://www.irs.gov/uac/Newsroom/IRS-Warns-of-Pervasive-Telephone-Scam
I suspect this is the number of an IRS phone scam. Caller insisted that there is legal action by the IRS and that I should call back. Having been the recipient of a similar scam before, I didn't call back. Caller appears to have an Indian accent.
I received the same phone message this morning at 7 a.m.! I thought it was a strange number and to be a recording. It looks to be a scam....I will not be calling this number back.
Got two "urgent" messages by a man claiming that the IRS was filing a lawsuit against me. Used the name Chris Rogers. Had a very slight foreign accent. The IRS doesn't make calls like this out of the blue. Won't be returning his calls. Will be blocking the number. Watch out!