The number called me at work.

Hi My Name is Robert Lawless. And this message is intended to contact you regarding an enforcement action executed by the US Treasury intending your serious attention. Ignoring this will be an intentional second attempt to avoid an issue of appearance for the magistrate judge or grand jury for a federal criminal offense.  The number to call is 347-344-5309.  I repeat, 347-344-5309.  I'd like you to contact us so we can help you.

SCAM - ignore it.  The IRS mails letters if there is a problem.

I received a call from this number on January 24 2016 at 4:10 pm. The message said something  about me being taken to court on criminal charges and to call immediately.  I didn't call.

Very similar message (to SZ) left early this afternoon today.  Name given was Robert Morris.  Clearly a scam and call won't be returned.  Will also block this number.