I received the same type of message...and needless to say it was scary. This must be some new form of tactic to get people to call. Before I called, I googled the number...I knew something made no sense. If there was anything that was "serious" a letter from the IRS or somewhere else would be mailed to you...this is what I was always taught in order to avoid scams.

Geez...the lengths people will go to.....

I received the same call from this number and same name hard accent and bad grammar.  Gues scammers are on full time.  

Officer Sean Marshall. thick accent. says its urgent. but doesn't leave a message. what an a-hole!

I got this call on a Saturday. It felt like a scam, but it's a good scare tactic- "there's a legal notice pressed against your name", "it's urgent that you return this call"- and I almost called back.  Thank goodness for google and sites like this!  Thanks for posting, everyone. I will not be returning Mr. Sean Marshall's call.  

Called my grandmother's house on 12/22 saying they have affidavit from the Crime Investigation Dept of the IRS. Do not call them back or just hang up. It's a scam.   I found this article on the IRS website: http://www.irs.gov/uac/Newsroom/IRS-Reiterate ... -Telephone-Scam  and you can report it here: http://www.treasury.gov/tigta/contact_report_scam.shtml