I also received a phone message from these scammers stating it was the IRS and that I was being sued. I do not owe any money to the IRS. When I called the number, some foreign guy answered with "Thank you for calling the Internal Revenue Service, how can I help you?" These people need to be stopped before some unwitting person gives away all their money!
Received a call 23 Jul 2015, left message "IRS is filing a lawsuit against you, call 425-541-3997". Checked number online, which I always do if number is unknown, and found the above comments. Thanks to everyone for sharing your info.
Received a message from 425-247-3057 saying I was being sued by the IRS. Called the number and I got a man with a heavy Indian accent who sounded like he was in a room full of people. For the love of all that is good, DO NOT fall for this scam!! The IRS would contact you in a much more official and efficient manner.