Received same scam call yesterday, and listened to the recorded message telling me the IRS was filing a lawsuit against me if I didn't call back. Of course, I didn't call back, knowing it was a fraud. Today I didn't answer, and their robodialer gave up after 3 rings.
Automated call from the IRS claiming this was a final notice and they were going to sue me. Gave me a number to call their "office" for more information. Yeah, right, the caller ID for a government agency is "wireless caller". Total scam